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  • Snow Leopard Permissions in Shared Folders reset on saving file

    - by jan
    I have several users who access their accounts on OSX through their windows machines over samba. As soon as they update/save a file, it sets the permissions to -rwxr----- which means no other users can read the files. This affects apache user, for example, so changes to their files under their Sites directory means Apache can no longer serve the pages. I've looked into /etc/smb.conf, /var/db/smb.conf, and /var/db/samba/smb.shares but I can't figure out how to force it to use the parent folders permissions. Thanks in advance.

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  • Is this a normal operating temperature range for a New Third-Generation MacBook Air (2.13 MHz, 120 G

    - by doug
    Even with just my text editor open (no web browser) and maybe the terminal, the baseline temperature is usually above 40 C. When i open 4-5 browser tabs in Safari (even if none of Sites have Flash) the temp can quickly go over 50 C. (In addition, i am observing these temps even though i have turned the fan up to 3000 rpms). (i have install smcFanControl on my MBA so i can see the temp in the menu bar.) So this means my MBA is running much warmer than my MBP; and in practice, it means that i have to be very careful how i use my MBA. Of course if i load a Site with Flash, it just freaks out, and often quickly goes above 65 C (I've installed a flash blocker to avoid this). Is anyone else observing this behavior? I have checked the Apple boards and sure enough, there are a lot of complaints, but nothing from Apple.

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  • How to protect an OS X Server from an anautorized physical connection?

    - by GJ
    Hi I have an OS X 10.6 server, which I administer via SSH and VNC (via SSH tunnel). I can't leave it at the login window since then VNC connections are refused. Therefore I currently leave it logged with my user account. Since it doesn't have a monitor attached, it doesn't go into screen saver mode, which means it doesn't require a password to retake control. This means it is very easy for anyone connecting a keyboard/mouse and monitor to take control of the system. The screen saver password protection, which I can't get to activate, unlike the system's login window, is perfectly compatible with VNC connections. How could I prevent such direct access to the server without connecting a monitor and without blocking my ability to connect with VNC? Thanks!

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  • How to protect an OS X Server from an unauthorized physical connection?

    - by GJ
    Hi I have an OS X 10.6 server, which I administer via SSH and VNC (via SSH tunnel). I can't leave it at the login window since then VNC connections are refused. Therefore I currently leave it logged with my user account. Since it doesn't have a monitor attached, it doesn't go into screen saver mode, which means it doesn't require a password to retake control. This means it is very easy for anyone connecting a keyboard/mouse and monitor to take control of the system. The screen saver password protection, which I can't get to activate, unlike the system's login window, is perfectly compatible with VNC connections. How could I prevent such direct access to the server without connecting a monitor and without blocking my ability to connect with VNC? Thanks!

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  • Admin mode on Procurve Switches

    - by stefan.at.wpf
    Not being a network expert, I spent some time configuring my network, until I found my mistake: On my HP ProCurve Switch 1810G, I thought that "Admin mode" means whether the administrative interface can be accessed from this port. Well, it means whether the port is enabled or not. Extract from the help function: Admin Mode - Select to enable the port-control administration state. Click to enable and have the port participate in the network.(Default : Enabled ) Well, of course I didn't read the help, because I didn't doubt it's for the adminsitrative interface and suspected an error somewhere else. Anyway, I am wondering if that is a commonly used term for enabling/disabling ports or if HP just wanted to make my life harder? I can't understand why this option isn't just called "Enable port"!? Here's a screenshot of how it looks in the web interface (yeah, shame on me for using a web interface)

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  • Understanding top output in Linux

    - by Rayne
    Hi, I'm trying to determine the CPU usage of a program by looking at the output from Top in Linux. I understand that %us means userspace and %sy means system/kernel etc. But say I see 100%us. Does this mean that the CPU is really only doing useful work? What if a CPU is tied up waiting for resources that are not avaliable, or cache misses, would it also show up in the %us column, or any other column? Thank you.

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  • Compiling Assembly Manually [migrated]

    - by John Smith
    I am having trouble with translating a specific line in assembly to machine code for the Nios II. I have successfully compiled these lines: START_TIMER = 0xF68C r0 = 0x0 r8 = 0x8 label = 50000 addi r8, r8, %lo(label) - 01000 01000 1100001101010000 000100 subi r8, r8, 1 - 01000 01000 1111111111111111 000100 bne r8, r0, START_TIMER - 01000 00000 1111011010001100 011110 The line in question that I have trouble with is this one: orhi r8, r0, %hiadj(label) As explained in the handbook linked above, "%lo" means "Extract bits [15..0] of immed32" and "%hiadj" means "Extract bits [31..16] and adds bit 15 of immed32". However, 50000 in binary is 1100001101010000, and is therefore a 16 bit number. As far as I can see, it doesn't contain any bits between 16 and 31. I tried with 0000000000000001, but it's incorrect. What am I doing wrong?

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  • How to add delay in autologin

    - by raj
    I enabled autologin in my system (CentOS 6.2) for that I edited this file /etc/gdm/custom.conf In that I entered this code [daemon] AutomaticLoginEnable=true AutomaticLogin=test Here test means one account name, for that account autologin is working but the problem is not possible to logout. That is because everytime while I logout it will go to gdm(graphical display manager) and there it Again checks for account test. It is available right so it will again login to same account. Here I want add delay, that means it should wait for sometime, If no one login to any other account, then only test account will log. how to add delay?

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  • /data/tmp on database server?

    - by Mellon
    I am on a Linux ubuntu machine with MySQL installed. My teacher gave out an assignment which mentioned "copy cars.dat to /data/tmp on the MySQL database server" without any explanations, I do not know what is the "/data/tmp on database server" means exactly? Basically after that I need to execute SQL statement like LOAD DATA INFILE '/data/tmp/cars.dat' INTO TABLE cars So, what does copy cars.dat to /data/tmp on the database server means as there is no /data/tmp directory even? Personally, I checked /etc/mysql/my.cnf file, inside which there are definitions of : ... basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp ... Does it mean to copy cars.dat to the tmpdir which is just /tmp under root directory??

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  • How do I circumvent Spotify's updater for my regular users in Windows?

    - by cros
    I run a Windows Vista machine where I have Spotify installed. My account is the only account with administrator rights on the machine, which means only I can update Spotify. This means that any other user on the machine won't be able to run Spotify if there is an update that I haven't installed. Is there any way to circumvent this? EDIT: I tried setting up a task in the Task Scheduler to start spotify.exe with administrative rights any time someone logged in, which I hoped would allow an update, but it didn't, so I'm open to new suggestions.

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  • How to backup MySQL (mysqldump) when Memcached installed?

    - by cewebugil
    The server OS is CentOS, with Memcached installed Before Memcached installed, I use mysqldump -u root -p --lock-tables --add-locks --disable-keys --skip-extended-insert --quick wcraze > /var/backup/backup.sql But now, Memcached has been installed. According to Wikipedia; When the table is full, subsequent inserts cause older data to be purged in least recently used (LRU) order. This means new data entry is not directly saved in MySQL, but saved in Memcached instead, until limit_maxbytes is full, the least accessed data will be saved in MySQL. This means, some data is not in the MySQL but in Memcached. So, when backup, the new entry is not in the backup data What is the right way to backup?

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  • How to reliably synchronise file servers between London and Shanghai?

    - by Andy S
    We have two offices, one in London and one in Shanghai, each needing to be able to access the same set of files. This means we need a solid, speedy means of synchronising a set of folders between servers at either office. They're likely to be Windows servers, but we could look at Linux boxes if the software side makes more sense on *nix. We've considered Rsync, Unison, Gluster, and a few other options, but none of them seem capable of reliably keeping the servers in sync between such distant office locations. Each office is on DSL connectivity over the open internet, so encryption is also a factor. Does anyone have any hints for getting the servers synchronising in as close to real time as possible, without dying constantly? Andy

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  • my laptop ibm thinkpad x32 showing black screen after booting

    - by forweb
    Thanks in advance. Well i have a laptop of IBM thinkpad x32. Windowx xp installed. So, the problem is that: The basic problem is the Black Screen but it's not means that laptop doesn't power-up or boot-up, sometimes after booting, screen will off and notable thing is that after black screen computer is still running all keyboard lights are on, and when i tried to again start it, it will boot ok but after some time screen will gone, and sometimes this happens during booting screen, even sometimes screen black out at win XP user login page, means after some seconds or min screen will gone. Hope you can understand my problem

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  • Is there a terminal that features sliding like guake and screen spliting like terminator on Linux?

    - by e-satis
    Sliding means I got the terminal always in background and I can call it with a shortcut, and it will slide down from the top of the screen like in Quake (which why the most known terminal implementing it is called guake). Splitting terminal means I can seen in one terminal tab several shells, like with screen or tmux. But I can also take the focus on each part of the terminal by clicking on it, not just with a 4 keys keyboard shortcut. Which terminator let me do. Is there a terminal that features both on Linux ? Even something I can pay for.

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  • HP DL160 G6 memory PC3-10600R vs PC3-10600E

    - by Jeremy Hajek
    I am using a HP DL 160 G6 server that according to specs takes PC3 Registered or Unbuffered. When I combine the two types of memory below the system will not POST. When I use just the first type of memory listed the system will POST. I have two pieces of HP memory that came with the server labeled PC3-10600E-9-10-E0 and then I have some Crucial memory labeled PC3-10600R-9-10-B0 I wager that the R means Registered memory and the E means ECC - then shouldn't the crucial memory boot with the system according to the HP specs? Or does the E mean it is Unbuffered and therefore I shouldn't mix and match as according to this HP memory config doc?

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  • small Windows network w/ printer issue

    - by user33666
    printer 1 connected to the desktop printer 2 connected to the same desktop that desktop is connected via Cat 5 to a wireless router a notebook is connected to that same router via WiFi The desktop Control Panel has just been reconfigured to share printers. (I assume this means that the desktop will now allow a notebook coming through the router to be able to access the two printers that are presently hooked up via the desktop--am I correct? Is that what it means?) The desktop can still print to either printer. It is presently okay. This notebook/printer relationship is a new configuration. The notebook, however, can't print at all (yet it can access the internet just fine). Any suggestions for it to be able to access the printers and be able to print via the desktop via the router? Thank you for any assistance.

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  • 1K incoming http post requests per second, each with a 10-50K file

    - by Blankman
    I'm trying to figure out what kind of server setup I will need to support: 1K http post requests per second each post will contain a xml file between 5-50K (average of 25 kilobytes) Even if I get a 100 Mb/s connection with my dedicated box (they usually give 10 Mb/s but you can upgrade), from my calculations that is about 12K kb/s which means about 480 25kb files per second. So this means I need around 3 servers then, each with 100 Mb/s connection. Would a single server running HAProxy be able to redirect the requests to other servers or does this mean I need to get something else that can handle more than 100 Mb/s to proxy things out to the other servers? If my math is off I'd appreciate any corrections you may have.

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  • Any way to overwrite (not merge) Outlook contacts when importing from a file?

    - by Dan
    I'm trying to create a contact list for Outlook 2010 that will contain contact information for every person in my company. I intend on keeping the list current, which means I will be manually adding new employees to the contact list, and removing contacts who no longer work here. The contact list will reside in its own subfolder within the Outlook Contacts folder. I want to periodically export this contact list as a .csv file, and allow the other employees in the company to import it into Outlook on their own computer, thus providing them with a comprehensive and up-to-date company contact list. The problem is, Outlook 2010 only wants to merge contact lists, not overwrite them. This means that any contacts who are no longer with the company will not be removed from the contact lists on employee stations. Is there any way to force Outlook 2010 to overwrite the contact list? Oh how I long for the days of Outlook 2003 and its tidy .pab files.

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  • How I can make my windows look like mac using any software or utilities?

    - by user33631
    I am currently using Windows classic mode in Win server 2008 r2. Can I get mac like themes in windows. Like When I run Photoshop, SongBird or other apps they have interface quite similar with Mac. Does someone know how it's possible to get a mac like look in windows (compatible to win 7). My simply means that something that make my windows's themes color like mac. Like I can run firefox by using themes but i want now for every apps means the three button on top titlebar and interface.

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  • Alow Plesk access (login) only for one domain

    - by crimson93
    Hope someone is able to help me. :) I have 4 domains registered, and all of them are using the same server. That means, they have the same IP-Address. Thats okay, but at the moment it is possible to access the plesk using ":8443" with all domains. But I would like to permit access to plesk only for 1 domain! That means, if enter: "https:// domainexample1:8443" it should allow the access to plesk. If I enter: "https:// domainexample2:8443" it should forbid. How can I configure this, or change the settings? Thanks in advance! :) Best regards

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  • SQL SERVER – Shrinking NDF and MDF Files – Readers’ Opinion

    - by pinaldave
    Previously, I had written a blog post about SQL SERVER – Shrinking NDF and MDF Files – A Safe Operation. After that, I have written the following blog post that talks about the advantage and disadvantage of Shrinking and why one should not be Shrinking a file SQL SERVER – SHRINKFILE and TRUNCATE Log File in SQL Server 2008. On this subject, SQL Server Expert Imran Mohammed left an excellent comment. I just feel that his comment is worth a big article itself. For everybody to read his wonderful explanation, I am posting this blog post here. Thanks Imran! Shrinking Database always creates performance degradation and increases fragmentation in the database. I suggest that you keep that in mind before you start reading the following comment. If you are going to say Shrinking Database is bad and evil, here I am saying it first and loud. Now, the comment of Imran is written while keeping in mind only the process showing how the Shrinking Database Operation works. Imran has already explained his understanding and requests further explanation. I have removed the Best Practices section from Imran’s comments, as there are a few corrections. Comments from Imran - Before I explain to you the concept of Shrink Database, let us understand the concept of Database Files. When we create a new database inside the SQL Server, it is typical that SQl Server creates two physical files in the Operating System: one with .MDF Extension, and another with .LDF Extension. .MDF is called as Primary Data File. .LDF is called as Transactional Log file. If you add one or more data files to a database, the physical file that will be created in the Operating System will have an extension of .NDF, which is called as Secondary Data File; whereas, when you add one or more log files to a database, the physical file that will be created in the Operating System will have the same extension as .LDF. The questions now are, “Why does a new data file have a different extension (.NDF)?”, “Why is it called as a secondary data file?” and, “Why is .MDF file called as a primary data file?” Answers: Note: The following explanation is based on my limited knowledge of SQL Server, so experts please do comment. A data file with a .MDF extension is called a Primary Data File, and the reason behind it is that it contains Database Catalogs. Catalogs mean Meta Data. Meta Data is “Data about Data”. An example for Meta Data includes system objects that store information about other objects, except the data stored by the users. sysobjects stores information about all objects in that database. sysindexes stores information about all indexes and rows of every table in that database. syscolumns stores information about all columns that each table has in that database. sysusers stores how many users that database has. Although Meta Data stores information about other objects, it is not the transactional data that a user enters; rather, it’s a system data about the data. Because Primary Data File (.MDF) contains important information about the database, it is treated as a special file. It is given the name Primary Data file because it contains the Database Catalogs. This file is present in the Primary File Group. You can always create additional objects (Tables, indexes etc.) in the Primary data file (This file is present in the Primary File group), by mentioning that you want to create this object under the Primary File Group. Any additional data file that you add to the database will have only transactional data but no Meta Data, so that’s why it is called as the Secondary Data File. It is given the extension name .NDF so that the user can easily identify whether a specific data file is a Primary Data File or a Secondary Data File(s). There are many advantages of storing data in different files that are under different file groups. You can put your read only in the tables in one file (file group) and read-write tables in another file (file group) and take a backup of only the file group that has read the write data, so that you can avoid taking the backup of a read-only data that cannot be altered. Creating additional files in different physical hard disks also improves I/O performance. A real-time scenario where we use Files could be this one: Let’s say you have created a database called MYDB in the D-Drive which has a 50 GB space. You also have 1 Database File (.MDF) and 1 Log File on D-Drive and suppose that all of that 50 GB space has been used up and you do not have any free space left but you still want to add an additional space to the database. One easy option would be to add one more physical hard disk to the server, add new data file to MYDB database and create this new data file in a new hard disk then move some of the objects from one file to another, and put the file group under which you added new file as default File group, so that any new object that is created gets into the new files, unless specified. Now that we got a basic idea of what data files are, what type of data they store and why they are named the way they are, let’s move on to the next topic, Shrinking. First of all, I disagree with the Microsoft terminology for naming this feature as “Shrinking”. Shrinking, in regular terms, means to reduce the size of a file by means of compressing it. BUT in SQL Server, Shrinking DOES NOT mean compressing. Shrinking in SQL Server means to remove an empty space from database files and release the empty space either to the Operating System or to SQL Server. Let’s examine this through an example. Let’s say you have a database “MYDB” with a size of 50 GB that has a free space of about 20 GB, which means 30GB in the database is filled with data and the 20 GB of space is free in the database because it is not currently utilized by the SQL Server (Database); it is reserved and not yet in use. If you choose to shrink the database and to release an empty space to Operating System, and MIND YOU, you can only shrink the database size to 30 GB (in our example). You cannot shrink the database to a size less than what is filled with data. So, if you have a database that is full and has no empty space in the data file and log file (you don’t have an extra disk space to set Auto growth option ON), YOU CANNOT issue the SHRINK Database/File command, because of two reasons: There is no empty space to be released because the Shrink command does not compress the database; it only removes the empty space from the database files and there is no empty space. Remember, the Shrink command is a logged operation. When we perform the Shrink operation, this information is logged in the log file. If there is no empty space in the log file, SQL Server cannot write to the log file and you cannot shrink a database. Now answering your questions: (1) Q: What are the USEDPAGES & ESTIMATEDPAGES that appear on the Results Pane after using the DBCC SHRINKDATABASE (NorthWind, 10) ? A: According to Books Online (For SQL Server 2000): UsedPages: the number of 8-KB pages currently used by the file. EstimatedPages: the number of 8-KB pages that SQL Server estimates the file could be shrunk down to. Important Note: Before asking any question, make sure you go through Books Online or search on the Google once. The reasons for doing so have many advantages: 1. If someone else already has had this question before, chances that it is already answered are more than 50 %. 2. This reduces your waiting time for the answer. (2) Q: What is the difference between Shrinking the Database using DBCC command like the one above & shrinking it from the Enterprise Manager Console by Right-Clicking the database, going to TASKS & then selecting SHRINK Option, on a SQL Server 2000 environment? A: As far as my knowledge goes, there is no difference, both will work the same way, one advantage of using this command from query analyzer is, your console won’t be freezed. You can do perform your regular activities using Enterprise Manager. (3) Q: What is this .NDF file that is discussed above? I have never heard of it. What is it used for? Is it used by end-users, DBAs or the SERVER/SYSTEM itself? A: .NDF File is a secondary data file. You never heard of it because when database is created, SQL Server creates database by default with only 1 data file (.MDF) and 1 log file (.LDF) or however your model database has been setup, because a model database is a template used every time you create a new database using the CREATE DATABASE Command. Unless you have added an extra data file, you will not see it. This file is used by the SQL Server to store data which are saved by the users. Hope this information helps. I would like to as the experts to please comment if what I understand is not what the Microsoft guys meant. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Readers Contribution, Readers Question, SQL, SQL Authority, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Option Trading: Getting the most out of the event session options

    - by extended_events
    You can control different aspects of how an event session behaves by setting the event session options as part of the CREATE EVENT SESSION DDL. The default settings for the event session options are designed to handle most of the common event collection situations so I generally recommend that you just use the defaults. Like everything in the real world though, there are going to be a handful of “special cases” that require something different. This post focuses on identifying the special cases and the correct use of the options to accommodate those cases. There is a reason it’s called Default The default session options specify a total event buffer size of 4 MB with a 30 second latency. Translating this into human terms; this means that our default behavior is that the system will start processing events from the event buffer when we reach about 1.3 MB of events or after 30 seconds, which ever comes first. Aside: What’s up with the 1.3 MB, I thought you said the buffer was 4 MB?The Extended Events engine takes the total buffer size specified by MAX_MEMORY (4MB by default) and divides it into 3 equally sized buffers. This is done so that a session can be publishing events to one buffer while other buffers are being processed. There are always at least three buffers; how to get more than three is covered later. Using this configuration, the Extended Events engine can “keep up” with most event sessions on standard workloads. Why is this? The fact is that most events are small, really small; on the order of a couple hundred bytes. Even when you start considering events that carry dynamically sized data (eg. binary, text, etc.) or adding actions that collect additional data, the total size of the event is still likely to be pretty small. This means that each buffer can likely hold thousands of events before it has to be processed. When the event buffers are finally processed there is an economy of scale achieved since most targets support bulk processing of the events so they are processed at the buffer level rather than the individual event level. When all this is working together it’s more likely that a full buffer will be processed and put back into the ready queue before the remaining buffers (remember, there are at least three) are full. I know what you’re going to say: “My server is exceptional! My workload is so massive it defies categorization!” OK, maybe you weren’t going to say that exactly, but you were probably thinking it. The point is that there are situations that won’t be covered by the Default, but that’s a good place to start and this post assumes you’ve started there so that you have something to look at in order to determine if you do have a special case that needs different settings. So let’s get to the special cases… What event just fired?! How about now?! Now?! If you believe the commercial adage from Heinz Ketchup (Heinz Slow Good Ketchup ad on You Tube), some things are worth the wait. This is not a belief held by most DBAs, particularly DBAs who are looking for an answer to a troubleshooting question fast. If you’re one of these anxious DBAs, or maybe just a Program Manager doing a demo, then 30 seconds might be longer than you’re comfortable waiting. If you find yourself in this situation then consider changing the MAX_DISPATCH_LATENCY option for your event session. This option will force the event buffers to be processed based on your time schedule. This option only makes sense for the asynchronous targets since those are the ones where we allow events to build up in the event buffer – if you’re using one of the synchronous targets this option isn’t relevant. Avoid forgotten events by increasing your memory Have you ever had one of those days where you keep forgetting things? That can happen in Extended Events too; we call it dropped events. In order to optimizes for server performance and help ensure that the Extended Events doesn’t block the server if to drop events that can’t be published to a buffer because the buffer is full. You can determine if events are being dropped from a session by querying the dm_xe_sessions DMV and looking at the dropped_event_count field. Aside: Should you care if you’re dropping events?Maybe not – think about why you’re collecting data in the first place and whether you’re really going to miss a few dropped events. For example, if you’re collecting query duration stats over thousands of executions of a query it won’t make a huge difference to miss a couple executions. Use your best judgment. If you find that your session is dropping events it means that the event buffer is not large enough to handle the volume of events that are being published. There are two ways to address this problem. First, you could collect fewer events – examine you session to see if you are over collecting. Do you need all the actions you’ve specified? Could you apply a predicate to be more specific about when you fire the event? Assuming the session is defined correctly, the next option is to change the MAX_MEMORY option to a larger number. Picking the right event buffer size might take some trial and error, but a good place to start is with the number of dropped events compared to the number you’ve collected. Aside: There are three different behaviors for dropping events that you specify using the EVENT_RETENTION_MODE option. The default is to allow single event loss and you should stick with this setting since it is the best choice for keeping the impact on server performance low.You’ll be tempted to use the setting to not lose any events (NO_EVENT_LOSS) – resist this urge since it can result in blocking on the server. If you’re worried that you’re losing events you should be increasing your event buffer memory as described in this section. Some events are too big to fail A less common reason for dropping an event is when an event is so large that it can’t fit into the event buffer. Even though most events are going to be small, you might find a condition that occasionally generates a very large event. You can determine if your session is dropping large events by looking at the dm_xe_sessions DMV once again, this time check the largest_event_dropped_size. If this value is larger than the size of your event buffer [remember, the size of your event buffer, by default, is max_memory / 3] then you need a large event buffer. To specify a large event buffer you set the MAX_EVENT_SIZE option to a value large enough to fit the largest event dropped based on data from the DMV. When you set this option the Extended Events engine will create two buffers of this size to accommodate these large events. As an added bonus (no extra charge) the large event buffer will also be used to store normal events in the cases where the normal event buffers are all full and waiting to be processed. (Note: This is just a side-effect, not the intended use. If you’re dropping many normal events then you should increase your normal event buffer size.) Partitioning: moving your events to a sub-division Earlier I alluded to the fact that you can configure your event session to use more than the standard three event buffers – this is called partitioning and is controlled by the MEMORY_PARTITION_MODE option. The result of setting this option is fairly easy to explain, but knowing when to use it is a bit more art than science. First the science… You can configure partitioning in three ways: None, Per NUMA Node & Per CPU. This specifies the location where sets of event buffers are created with fairly obvious implication. There are rules we follow for sub-dividing the total memory (specified by MAX_MEMORY) between all the event buffers that are specific to the mode used: None: 3 buffers (fixed)Node: 3 * number_of_nodesCPU: 2.5 * number_of_cpus Here are some examples of what this means for different Node/CPU counts: Configuration None Node CPU 2 CPUs, 1 Node 3 buffers 3 buffers 5 buffers 6 CPUs, 2 Node 3 buffers 6 buffers 15 buffers 40 CPUs, 5 Nodes 3 buffers 15 buffers 100 buffers   Aside: Buffer size on multi-processor computersAs the number of Nodes or CPUs increases, the size of the event buffer gets smaller because the total memory is sub-divided into more pieces. The defaults will hold up to this for a while since each buffer set is holding events only from the Node or CPU that it is associated with, but at some point the buffers will get too small and you’ll either see events being dropped or you’ll get an error when you create your session because you’re below the minimum buffer size. Increase the MAX_MEMORY setting to an appropriate number for the configuration. The most likely reason to start partitioning is going to be related to performance. If you notice that running an event session is impacting the performance of your server beyond a reasonably expected level [Yes, there is a reasonably expected level of work required to collect events.] then partitioning might be an answer. Before you partition you might want to check a few other things: Is your event retention set to NO_EVENT_LOSS and causing blocking? (I told you not to do this.) Consider changing your event loss mode or increasing memory. Are you over collecting and causing more work than necessary? Consider adding predicates to events or removing unnecessary events and actions from your session. Are you writing the file target to the same slow disk that you use for TempDB and your other high activity databases? <kidding> <not really> It’s always worth considering the end to end picture – if you’re writing events to a file you can be impacted by I/O, network; all the usual stuff. Assuming you’ve ruled out the obvious (and not so obvious) issues, there are performance conditions that will be addressed by partitioning. For example, it’s possible to have a successful event session (eg. no dropped events) but still see a performance impact because you have many CPUs all attempting to write to the same free buffer and having to wait in line to finish their work. This is a case where partitioning would relieve the contention between the different CPUs and likely reduce the performance impact cause by the event session. There is no DMV you can check to find these conditions – sorry – that’s where the art comes in. This is  largely a matter of experimentation. On the bright side you probably won’t need to to worry about this level of detail all that often. The performance impact of Extended Events is significantly lower than what you may be used to with SQL Trace. You will likely only care about the impact if you are trying to set up a long running event session that will be part of your everyday workload – sessions used for short term troubleshooting will likely fall into the “reasonably expected impact” category. Hey buddy – I think you forgot something OK, there are two options I didn’t cover: STARTUP_STATE & TRACK_CAUSALITY. If you want your event sessions to start automatically when the server starts, set the STARTUP_STATE option to ON. (Now there is only one option I didn’t cover.) I’m going to leave causality for another post since it’s not really related to session behavior, it’s more about event analysis. - Mike Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • ASP.NET Web Forms Extensibility: Providers

    - by Ricardo Peres
    Introduction This will be the first of a number of posts on ASP.NET extensibility. At this moment I don’t know exactly how many will be and I only know a couple of subjects that I want to talk about, so more will come in the next days. I have the sensation that the providers offered by ASP.NET are not widely know, although everyone uses, for example, sessions, they may not be aware of the extensibility points that Microsoft included. This post won’t go into details of how to configure and extend each of the providers, but will hopefully give some pointers on that direction. Canonical These are the most widely known and used providers, coming from ASP.NET 1, chances are, you have used them already. Good support for invoking client side, either from a .NET application or from JavaScript. Lots of server-side controls use them, such as the Login control for example. Membership The Membership provider is responsible for managing registered users, including creating new ones, authenticating them, changing passwords, etc. ASP.NET comes with two implementations, one that uses a SQL Server database and another that uses the Active Directory. The base class is Membership and new providers are registered on the membership section on the Web.config file, as well as parameters for specifying minimum password lengths, complexities, maximum age, etc. One reason for creating a custom provider would be, for example, storing membership information in a different database engine. 1: <membership defaultProvider="MyProvider"> 2: <providers> 3: <add name="MyProvider" type="MyClass, MyAssembly"/> 4: </providers> 5: </membership> Role The Role provider assigns roles to authenticated users. The base class is Role and there are three out of the box implementations: XML-based, SQL Server and Windows-based. Also registered on Web.config through the roleManager section, where you can also say if your roles should be cached on a cookie. If you want your roles to come from a different place, implement a custom provider. 1: <roleManager defaultProvider="MyProvider"> 2: <providers> 3: <add name="MyProvider" type="MyClass, MyAssembly" /> 4: </providers> 5: </roleManager> Profile The Profile provider allows defining a set of properties that will be tied and made available to authenticated or even anonymous ones, which must be tracked by using anonymous authentication. The base class is Profile and the only included implementation stores these settings in a SQL Server database. Configured through profile section, where you also specify the properties to make available, a custom provider would allow storing these properties in different locations. 1: <profile defaultProvider="MyProvider"> 2: <providers> 3: <add name="MyProvider" type="MyClass, MyAssembly"/> 4: </providers> 5: </profile> Basic OK, I didn’t know what to call these, so Basic is probably as good as a name as anything else. Not supported client-side (doesn’t even make sense). Session The Session provider allows storing data tied to the current “session”, which is normally created when a user first accesses the site, even when it is not yet authenticated, and remains all the way. The base class and only included implementation is SessionStateStoreProviderBase and it is capable of storing data in one of three locations: In the process memory (default, not suitable for web farms or increased reliability); A SQL Server database (best for reliability and clustering); The ASP.NET State Service, which is a Windows Service that is installed with the .NET Framework (ok for clustering). The configuration is made through the sessionState section. By adding a custom Session provider, you can store the data in different locations – think for example of a distributed cache. 1: <sessionState customProvider=”MyProvider”> 2: <providers> 3: <add name=”MyProvider” type=”MyClass, MyAssembly” /> 4: </providers> 5: </sessionState> Resource A not so known provider, allows you to change the origin of localized resource elements. By default, these come from RESX files and are used whenever you use the Resources expression builder or the GetGlobalResourceObject and GetLocalResourceObject methods, but if you implement a custom provider, you can have these elements come from some place else, such as a database. The base class is ResourceProviderFactory and there’s only one internal implementation which uses these RESX files. Configuration is through the globalization section. 1: <globalization resourceProviderFactoryType="MyClass, MyAssembly" /> Health Monitoring Health Monitoring is also probably not so well known, and actually not a good name for it. First, in order to understand what it does, you have to know that ASP.NET fires “events” at specific times and when specific things happen, such as when logging in, an exception is raised. These are not user interface events and you can create your own and fire them, nothing will happen, but the Health Monitoring provider will detect it. You can configure it to do things when certain conditions are met, such as a number of events being fired in a certain amount of time. You define these rules and route them to a specific provider, which must inherit from WebEventProvider. Out of the box implementations include sending mails, logging to a SQL Server database, writing to the Windows Event Log, Windows Management Instrumentation, the IIS 7 Trace infrastructure or the debugger Trace. Its configuration is achieved by the healthMonitoring section and a reason for implementing a custom provider would be, for example, locking down a web application in the event of a significant number of failed login attempts occurring in a small period of time. 1: <healthMonitoring> 2: <providers> 3: <add name="MyProvider" type="MyClass, MyAssembly"/> 4: </providers> 5: </healthMonitoring> Sitemap The Sitemap provider allows defining the site’s navigation structure and associated required permissions for each node, in a tree-like fashion. Usually this is statically defined, and the included provider allows it, by supplying this structure in a Web.sitemap XML file. The base class is SiteMapProvider and you can extend it in order to supply you own source for the site’s structure, which may even be dynamic. Its configuration must be done through the siteMap section. 1: <siteMap defaultProvider="MyProvider"> 2: <providers><add name="MyProvider" type="MyClass, MyAssembly" /> 3: </providers> 4: </siteMap> Web Part Personalization Web Parts are better known by SharePoint users, but since ASP.NET 2.0 they are included in the core Framework. Web Parts are server-side controls that offer certain possibilities of configuration by clients visiting the page where they are located. The infrastructure handles this configuration per user or globally for all users and this provider is responsible for just that. The base class is PersonalizationProvider and the only included implementation stores settings on SQL Server. Add new providers through the personalization section. 1: <webParts> 2: <personalization defaultProvider="MyProvider"> 3: <providers> 4: <add name="MyProvider" type="MyClass, MyAssembly"/> 5: </providers> 6: </personalization> 7: </webParts> Build The Build provider is responsible for compiling whatever files are present on your web folder. There’s a base class, BuildProvider, and, as can be expected, internal implementations for building pages (ASPX), master pages (Master), user web controls (ASCX), handlers (ASHX), themes (Skin), XML Schemas (XSD), web services (ASMX, SVC), resources (RESX), browser capabilities files (Browser) and so on. You would write a build provider if you wanted to generate code from any kind of non-code file so that you have strong typing at development time. Configuration goes on the buildProviders section and it is per extension. 1: <buildProviders> 2: <add extension=".ext" type="MyClass, MyAssembly” /> 3: </buildProviders> New in ASP.NET 4 Not exactly new since they exist since 2010, but in ASP.NET terms, still new. Output Cache The Output Cache for ASPX pages and ASCX user controls is now extensible, through the Output Cache provider, which means you can implement a custom mechanism for storing and retrieving cached data, for example, in a distributed fashion. The base class is OutputCacheProvider and the only implementation is private. Configuration goes on the outputCache section and on each page and web user control you can choose the provider you want to use. 1: <caching> 2: <outputCache defaultProvider="MyProvider"> 3: <providers> 4: <add name="MyProvider" type="MyClass, MyAssembly"/> 5: </providers> 6: </outputCache> 7: </caching> Request Validation A big change introduced in ASP.NET 4 (and refined in 4.5, by the way) is the introduction of extensible request validation, by means of a Request Validation provider. This means we are not limited to either enabling or disabling event validation for all pages or for a specific page, but we now have fine control over each of the elements of the request, including cookies, headers, query string and form values. The base provider class is RequestValidator and the configuration goes on the httpRuntime section. 1: <httpRuntime requestValidationType="MyClass, MyAssembly" /> Browser Capabilities The Browser Capabilities provider is new in ASP.NET 4, although the concept exists from ASP.NET 2. The idea is to map a browser brand and version to its supported capabilities, such as JavaScript version, Flash support, ActiveX support, and so on. Previously, this was all hardcoded in .Browser files located in %WINDIR%\Microsoft.NET\Framework(64)\vXXXXX\Config\Browsers, but now you can have a class inherit from HttpCapabilitiesProvider and implement your own mechanism. Register in on the browserCaps section. 1: <browserCaps provider="MyClass, MyAssembly" /> Encoder The Encoder provider is responsible for encoding every string that is sent to the browser on a page or header. This includes for example converting special characters for their standard codes and is implemented by the base class HttpEncoder. Another implementation takes care of Anti Cross Site Scripting (XSS) attacks. Build your own by inheriting from one of these classes if you want to add some additional processing to these strings. The configuration will go on the httpRuntime section. 1: <httpRuntime encoderType="MyClass, MyAssembly" /> Conclusion That’s about it for ASP.NET providers. It was by no means a thorough description, but I hope I managed to raise your interest on this subject. There are lots of pointers on the Internet, so I only included direct references to the Framework classes and configuration sections. Stay tuned for more extensibility!

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  • C#.NET vs VB.NET, Which language is better?

    Features I cannot say any language good or bad as long as it's compiler can produce MSIL can run under .NET CLR. If someone says C# has more futures, you can understand that those new features are of C# compiler but not .NET, because if C# has a specific future then CLR cannot understand them. So the new features of C# will have to convert to the code understood by CLR eventually. that means the new features are developed for C# compiler basically to facilitates the developer to write their code in better way. so that means no difference in feature list between C# and VB.NET if you think in CLR perspective. Ease of writing Code I feel writing code in C# is easy, because my background is C and C++, Java, syntaxes very are similar. I assume most developers feel the same. Readability But some people say VB.NET code most readable for the members who are from non technical background, because keywords are generally in English rather special charectors. No of Projects in Market I assume 80 percent of market uses C# in their .NET development. for example in my company many projects are there .nET and all are using C#. Productivity & Experience though the feature list is same, generally developers wants to write code in their familiar languages. because it increase the productivity. Hope this helps to choose the language which suits for you. span.fullpost {display:none;}

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