Search Results

Search found 15401 results on 617 pages for 'memory optimization'.

Page 54/617 | < Previous Page | 50 51 52 53 54 55 56 57 58 59 60 61  | Next Page >

  • Searching a process' memory on Linux

    - by Matt Joiner
    How can I search the memory state of an process in Linux? Specifically I wish to identify certain regions of interest, and peek at them at regular intervals, possibly occasionally poking new values. I suspect an answer may involve calls to ptrace(), and reading /proc/[pid]/mem, but need more to go on.

    Read the article

  • CoreData leak when reading a property

    - by Kamchatka
    Hello, I have the following code in a loop iterating over the different document objects: NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init]; [document primitiveValueForKey:@"data"]; [data writeToFile:filename atomically:NO]; [document.managedObjectContext refreshObject:document mergeChanges:NO]; [pool release]; The "data" property is a large blob (a 1MB image). And as I monitor the memory with the Allocation Instrument memory usage is increasing. I cannot find where the leak is coming from and how to remove it. Thanks!

    Read the article

  • Visual Studio Memory Hog

    - by gentoo_drummer
    I have installed Visual Studio Express Web Developer 2010 and boy it really slows my system down a lot. Is there a way to identify the services like SQL Server and set them to manual so I can avoid all my memory resources been occupied when not using Visual Studio? Is it just SQL Express the problem or are there any other things I should consider disabling in order to have a fast and reliable system when not using Visual Studio? Thanks!

    Read the article

  • sql UPDATE, a calculation is used multiple times, can it just be calculated once?

    - by Zachery Delafosse
    UPDATE `play` SET `counter1` = `counter1` + LEAST(`maxchange`, FLOOR(`x` / `y`) ), `counter2` = `counter2` - LEAST(`maxchange`, FLOOR(`x` / `y`) ), `x` = MOD(`x`, `y`) WHERE `x` `y` AND `maxchange` 0 As you can see, " LEAST(`maxchange`, FLOOR(`x` / `y`) ) " is used multiple times, but it should always have the same value. Is there a way to optimize this, to only calculate once? I'm coding this in PHP, for the record.

    Read the article

  • iPhone memory management, a newbie question

    - by Reuven
    Hi, I've seen in (Apple) sample code two types of ways of allocation memory, and am not sure I understand the difference and resulting behavior. // FAILS NSMutableArray *anArray = [NSMutableArray array]; [anArray release]; // WORKS NSMutableArray *anArray1 = [[NSMutableArray alloc] init]; [anArray release]; By "FAILS" I mean I get crashes/runtime warnings etc., and not always as soon as I call the release... Any explanation appreciated. Thanks

    Read the article

  • Why is Postgres doing a Hash in this query?

    - by Claudiu
    I have two tables: A and P. I want to get information out of all rows in A whose id is in a temporary table I created, tmp_ids. However, there is additional information about A in the P table, foo, and I want to get this info as well. I have the following query: SELECT A.H_id AS hid, A.id AS aid, P.foo, A.pos, A.size FROM tmp_ids, P, A WHERE tmp_ids.id = A.H_id AND P.id = A.P_id I noticed it going slowly, and when I asked Postgres to explain, I noticed that it combines tmp_ids with an index on A I created for H_id with a nested loop. However, it hashes all of P before doing a Hash join with the result of the first merge. P is quite large and I think this is what's taking all the time. Why would it create a hash there? P.id is P's primary key, and A.P_id has an index of its own.

    Read the article

  • Why would using a Temp table be faster than a nested query?

    - by Mongus Pong
    We are trying to optimise some of our queries. One query is doing the following: SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, INTO [#Gadget] FROM task t SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) as Client FROM [#Gadget] order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC DROP TABLE [#Gadget] (I have removed the complex subquery, cos I dont think its relevant other than to explain why this query has been done as a two stage process.) Now I would have thought it would be far more efficient to merge this down into a single query using subqueries as : SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) FROM ( SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, FROM task t ) as sub order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC This would give the optimiser better information to work out what was going on and avoid any temporary tables. It should be faster. But it turns out it is a lot slower. 8 seconds vs under 5 seconds. I cant work out why this would be the case as all my knowledge of databases imply that subqueries would always be faster than using temporary tables. Can anyone explain what could be going on!?!?

    Read the article

  • Class destructor memory handling in C++

    - by wyatt
    What potential memory leaks won't an implicit destructor handle? I know that if you have anything stored on the heap it won't handle it, and if you have a connection to a file or a database, that needs to be handled manually. Is there anything else? What about, say, non-base data types like vectors? Also, in an explicit destructor, need you destroy non-heap variables which would have been destroyed by the implicit, or are they handled automatically? Thanks

    Read the article

  • Why exactly is calling the destructor for the second time undefined behavior in C++?

    - by sharptooth
    As mentioned in this answer simply calling the destructor for the second time is already undefined behavior 12.4/14(3.8). For example: class Class { public: ~Class() {} }; // somewhere in code: { Class* object = new Class(); object->~Class(); delete object; // UB because at this point the destructor call is attempted again } In this example the class is designed in such a way that the destructor could be called multiple times - no things like double-deletion can happen. The memory is still allocated at the point where delete is called - the first destructor call doesn't call the ::operator delete() to release memory. For example, in Visual C++ 9 the above code looks working. Even C++ definition of UB doesn't directly prohibit things qualified as UB from working. So for the code above to break some implementation and/or platform specifics are required. Why exactly would the above code break and under what conditions?

    Read the article

  • Ruby: execute a binary file in memory?

    - by John
    Is it possible to read binary in ruby file and execute it directly in memory? for example something like this: x = IO.read('/bin/ls') execute(x) I tried system(x) but it doesn't work ArgumentError: string contains null byte

    Read the article

  • Main Memory Database with C++ Interface

    - by myahya
    I am looking for a main memory database with a C++ interface. I am looking for a database with a programmatic query interface and preferably one that works with native C++ types. SQLLite, for example, takes queries as string and needs to perform parsing ... which is time consuming. The operations I am looking for are: Creation of tables of arbitrary dimensions (number of attributes) capable of storing integer types. Support for insertion, deletion, selection, projection and (not a priority) joins.

    Read the article

  • Should i really use integer primary IDs [sql]

    - by arthurprs
    For example, i always generate an auto-increment field for the users table, but i also specifies an UNIQUE index on their usernames. There is situations that i first need to get the userId for a given username and then execute the desired query. Or use a JOIN in the desired query. It's 2 trips to the database or a JOIN vs. a varchar index The above is just an example There is a real performance benefit on INT over small VARCHAR indexes? Thanks in advance!

    Read the article

  • Pointers in For loops

    - by Bobby
    Quick question: I am a C# guy debugging a C++ app so I am not used to memory management. In the following code: for(int i = 0; i < TlmMsgDB.CMTGetTelemMsgDBCount(); i++) { CMTTelemetryMsgCls* telm = TlmMsgDB.CMTGetTelemetryMsg(i); CMT_SINT32_Tdef id = telm->CMTGetPackingMapID(); ManualScheduleTables.SetManualMsg(i,id); ManualScheduleTables.SetManExec(i,false); } Am I leaking memory every iteration b/c of CMTTelemetryMsgCls* telm = TlmMsgDB.CMTGetTelemetryMsg(i);? The "CMTGetTelemetryMsg(int)" method returns a pointer. Do I have to "delete telm;" at the end of each iteration?

    Read the article

  • sqlite eatingup memory on iPhone when doing insert

    - by kviksilver
    I am having problem with inserting data to sqlite database. char *update="INSERT OR REPLACE INTO ct_subject (id,id_parent, title, description, link, address, phone, pos_lat, pos_long, no_votes, avg_vote, photo, id_comerc, id_city, placement, type, timestamp, mail) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?);"; sqlite3_stmt *stmt; if(sqlite3_prepare_v2(database, update, -1, &stmt, nil) == SQLITE_OK){ sqlite3_bind_int(stmt, 1, [[[newCategories objectAtIndex:i] valueForKey:@"id"] intValue]); sqlite3_bind_int(stmt, 2, [[[newCategories objectAtIndex:i] valueForKey:@"id_parent"] intValue]); sqlite3_bind_text(stmt, 3, [[[newCategories objectAtIndex:i] valueForKey:@"title"] UTF8String], -1, NULL); sqlite3_bind_text(stmt, 4, [[[newCategories objectAtIndex:i] valueForKey:@"description"] UTF8String], -1, NULL); sqlite3_bind_text(stmt, 5, [[[newCategories objectAtIndex:i] valueForKey:@"link"] UTF8String], -1, NULL); sqlite3_bind_text(stmt, 6, [[[newCategories objectAtIndex:i] valueForKey:@"address"] UTF8String], -1, NULL); sqlite3_bind_text(stmt, 7, [[[newCategories objectAtIndex:i] valueForKey:@"phone"] UTF8String], -1, NULL); sqlite3_bind_text(stmt, 8, [[[newCategories objectAtIndex:i] valueForKey:@"pos_lat"] UTF8String], -1, NULL); sqlite3_bind_text(stmt, 9, [[[newCategories objectAtIndex:i] valueForKey:@"pos_long"] UTF8String], -1, NULL); sqlite3_bind_int(stmt, 10, [[[newCategories objectAtIndex:i] valueForKey:@"no_votes"] intValue]); sqlite3_bind_text(stmt, 11, [[[newCategories objectAtIndex:i] valueForKey:@"avg_vote"] UTF8String], -1, NULL); if ([[[newCategories objectAtIndex:i] valueForKey:@"photo"] length]!=0) { NSMutableString *webUrl = (NSMutableString *)[[NSMutableString alloc] initWithString:@"http://www.crotune.com/public/images/subjects/"]; [webUrl appendString:[[newCategories objectAtIndex:i] valueForKey:@"photo"]]; UIImage *myImage = [self getWebImage:webUrl]; if(myImage != nil){ sqlite3_bind_blob(stmt, 12, [UIImagePNGRepresentation(myImage) bytes], [UIImagePNGRepresentation(myImage) length], NULL); } else { sqlite3_bind_blob(stmt, 12, nil, -1, NULL); } [webUrl release]; [myImage release]; } else { sqlite3_bind_blob(stmt, 12, nil, -1, NULL); //NSLog(@" ne dodajem sliku2"); } sqlite3_bind_int(stmt, 13, [[[newCategories objectAtIndex:i] valueForKey:@"id_comerc"] intValue]); sqlite3_bind_int(stmt, 14, [[[newCategories objectAtIndex:i] valueForKey:@"id_city"] intValue]); sqlite3_bind_int(stmt, 15, [[[newCategories objectAtIndex:i] valueForKey:@"placement"] intValue]); sqlite3_bind_int(stmt, 16, [[[newCategories objectAtIndex:i] valueForKey:@"type"] intValue]); sqlite3_bind_int(stmt, 17, [[[newCategories objectAtIndex:i] valueForKey:@"timestamp"] intValue]); sqlite3_bind_text(stmt, 18, [[[newCategories objectAtIndex:i] valueForKey:@"mail"] UTF8String], -1, NULL); } if (sqlite3_step(stmt) != SQLITE_DONE) { NSLog(@"%s", sqlite3_errmsg(database)); NSAssert1(0,@"nemogu updateat table %s", errorMsg); } else { NSLog(@"Ubacio %d",i); }sqlite3_finalize(stmt); What happens is that it starts to eat memory until it finaly quits... On memory warning i close and open database again, I have set cache size to 50 as mentioned in some posts here, and tried putting query into statement - same result.. it just garbles mamory and app quits after 300 inserts on iphone or somewhere around 900 inserts on iPad... Any help would be appreciated..

    Read the article

  • How to create temporary files in memory visible for other process, using python

    - by LazyMiha
    Hello! I`m trying to write simple batch file generator in python. Batch file consist of about 30-50 lines of text and is passed to other applications. During the execution of script there a lot of calls to external applications. I want to create file in memory (like named pipes in win32). Is there any platform independ way? p.s. sorry for possible mistakes in text, I'm still learning English

    Read the article

  • How much memory is my iphone app using (from Simulator)

    - by Jonathan
    I know this has something to do with Instruments, but well it's kind of confusing and searching for Instruments on Google doesn't help much. I'd like to know how well my app runs, like how much memory it uses. I just don't know where to find something like: "As close as we can tell from the simulator you'll app will currently be using xx MBs of RAM on a real iphone device." I need help on how to get this information.

    Read the article

  • Memory Leaks - C

    - by sbsp
    Hi guys, Is there a good application (that has some kind of gui) for testing memory leaks in c code. I would really like to test my assignment/programme but being very new to this, i struggle with using the terminal to do things, especially using gdb for debugging (to me it feels like a blast from the past, where i could be using some visual debugger). Thanks for the help

    Read the article

  • memory size exceeded?

    - by asdas
    i have a form that submits data to a database, i have a function that looks like this: //connect foreach ($_POST as $key => $value) { $_POST[$key] = mysql_real_escape_string($value); } now when i post, SOMETIMES i get an error that says this: Allowed memory size of 268435456 bytes exhausted i figured out that when i do a linebreak, or press enter in the message field, then that is when it causes the error, otherwise it works normal. any ideas?

    Read the article

  • Overhead of calling tiny functions from a tight inner loop? [C++]

    - by John
    Say you see a loop like this one: for(int i=0; i<thing.getParent().getObjectModel().getElements(SOME_TYPE).count(); ++i) { thing.getData().insert( thing.GetData().Count(), thing.getParent().getObjectModel().getElements(SOME_TYPE)[i].getName() ); } if this was Java I'd probably not think twice. But in performance-critical sections of C++, it makes me want to tinker with it... however I don't know if the compiler is smart enough to make it futile. This is a made up example but all it's doing is inserting strings into a container. Please don't assume any of these are STL types, think in general terms about the following: Is having a messy condition in the for loop going to get evaluated each time, or only once? If those get methods are simply returning references to member variables on the objects, will they be inlined away? Would you expect custom [] operators to get optimized at all? In other words is it worth the time (in performance only, not readability) to convert it to something like: ElementContainer &source = thing.getParent().getObjectModel().getElements(SOME_TYPE); int num = source.count(); Store &destination = thing.getData(); for(int i=0;i<num;++i) { destination.insert(thing.GetData().Count(), source[i].getName(); } Remember, this is a tight loop, called millions of times a second. What I wonder is if all this will shave a couple of cycles per loop or something more substantial? Yes I know the quote about "premature optimisation". And I know that profiling is important. But this is a more general question about modern compilers, Visual Studio in particular.

    Read the article

< Previous Page | 50 51 52 53 54 55 56 57 58 59 60 61  | Next Page >