Different block sizes for partition and underlying logical disk on HP Raid Controller (Linux)

Posted by Wawrzek on Server Fault See other posts from Server Fault or by Wawrzek
Published on 2012-09-18T11:41:47Z Indexed on 2012/09/27 3:39 UTC
Read the original article Hit count: 452

Filed under:

linux

|

Performance

|

raid

|

hp

|

io

Following links collected in this thread I started to check blockdev and found the following output indicating different sizes for partition c0d9p1 and the underlying device (c0d9):

[root@machine ~]# blockdev --report /dev/cciss/c0d9
RO    RA   SSZ   BSZ   StartSec     Size    Device
rw   256   512  4096          0 3906963632  /dev/cciss/c0d9
[root@machine ~]# blockdev --report /dev/cciss/c0d9p1 
RO    RA   SSZ   BSZ   StartSec     Size    Device
rw   256   512  2048          1 3906959039  /dev/cciss/c0d9p1

We have a lot of small files, so yes the block size is smaller than normal. The device is a logical driver on an HP P410 raid controller, simple disk without any raid - RAID 0 on one disk to be precise. (Please note that above configuration is a feature not a bug).

Therefore, I have the following questions.

Can the above discrepancy in the block size affect disk performance?
Can I control the block size using hpacucli?

© Server Fault or respective owner

Related posts about linux

apt-get install and update fail

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I've got a problem with apt-get update and apt-get install ... commands . every time update or installing fails and errors are : Get:1 http://dl.google.com stable Release.gpg [198B] Ign http://dl.google.com/linux/chrome/deb/ stable/main Translation-en_US Get:2 http://dl… >>> More
kernel module compiling error

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
sh@ubuntu:/home/ccpp/helloworld$ make gcc-4.6 -O2 -DMODULE -D_KERNEL_ -W -Wall -Wstrict-prototypes -Wmissing-prototypes -isystem /lib/modules/`uname -r`/build/include -c -o hello-1.o hello-1.c hello-1.c:4:0: warning: "MODULE" redefined [enabled by default] <command-line>:0:0: note: this is… >>> More
Build-Essentials installation failing

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I am having trouble accessing the several critical header files that show to be a part of the build process. The "Ubuntu Software Center" shows "Build Essentials" as installed: Next I did the following two commands, which did not improve the problem: ~$ sudo apt-get install build-essential [sudo]… >>> More
Updating Debian kernel

as seen on Super User - Search for 'Super User'
I'm trying to update my Debian machine to 2.6.32-46 (which is the new stable). However, after doing apt-get update my apt-cache search linux-image shows me: linux-headers-2.6.32-5-486 - Header files for Linux 2.6.32-5-486 linux-headers-2.6.32-5-686-bigmem - Header files for Linux 2.6.32-5-686-bigmem linux-headers-2… >>> More
Serial connection over a single USB cable (Windows to linux, or linux to linux)

as seen on Server Fault - Search for 'Server Fault'
I'm helping out with a project for an embedded device that only has USB and no serial. This device is running Linux. These days, when we need to connect to a serial port on a device we typically use a USB to serial adapter (on something like a phone system or a load balancing device, etc). I would… >>> More

Related posts about Performance

Improving VPN performance - stronger encryption = more performance?

as seen on Server Fault - Search for 'Server Fault'
I have a site-to-site VPN set up with two SonicWall's (a TZ170 and a Pro1260). It was suggested to me that turning off encryption (so the VPN is tunneling only) would improve performance. (I'm not concerned with security, because the VPN is running over a trusted line.) Using FTP and HTTP transfers… >>> More
Inaccurate performance counter timer values in Windows Performance Monitor

as seen on Stack Overflow - Search for 'Stack Overflow'
I am implementing instrumentation within an application and have encountered an issue where the value that is displayed in Windows Performance Monitor from a PerformanceCounter is incongruent with the value that is recorded. I am using a Stopwatch to record the duration of a method execution, then… >>> More
Excel-based Performance Reviews transformed into Web Application for Performance Management

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
HR TMS provides enterprise talent management solutions for healthcare, retail and corporate customers, focusing on performance management, compensation management and succession planning. As the competency of nurses and other healthcare workers is critical, the government, via the Joint Commission… >>> More
How to save a perfmon Performance Counter as a textfile (Reliability and Performance Monitor Version

as seen on Server Fault - Search for 'Server Fault'
Now the file gets saved as blg, but I would like a txt versin to import in Excel. >>> More
SQLAuthority News – A Successful Performance Tuning Seminar at Pune – Dec 4-5, 2010

as seen on SQL Authority - Search for 'SQL Authority'
This is report to my third of very successful seminar event on SQL Server Performance Tuning. SQL Server Performance Tuning Seminar in Colombo was oversubscribed with total of 35 attendees. You can read the details over here SQLAuthority News – SQL Server Performance Optimizations Seminar – Grand… >>> More