optimise xfs for large partition
Hello, ok i am building new 64bit system with Gentoo and will have 650gb partition for storing my digital images. file will range in size from 3mb to 200mb with average about 20mb.
The partition is on a raid 1 array, the hardware for array is areca sata pciE raid card with 256mb ram, 500mhz processor, drives are 2x750gb Hitachi 7k1000. The 650gb array is set 128k stripe size. Now i have read and used the IBM article for setting up XFS but never for array this size. The guide talks about allocation groups Quote:
but following that a 650gb xfs partition will have very high number for allocations groups, is there max or should go with 1 for every 4gb? If do then allocation group number would be in the thousands!! Any tips for setting up xfs for this partition? cheers |
If the average file size is only 20MB, you have other things to worry about than allocation speed, especially on a computers with moderate specs (xfs tends to require a good deal of RAM to perform well) . Having too many allocation groups tends to become non-productive - if not counterproductive - beyond a certain point as performance will be affected by increased search activity.
It may be more interesting to focus on the area where xfs tends to lag a bit:file deletion. Xfs is noticeably slower in this respect than ext3 or reiser,especially when it comes to smaller files. Remember that xfs is optimized for large files, i.e. hundreds of megabytes. The good news is that you can get noticeable performance gains by manipulating the number and size of logbuffers. Just prepare your partition(s) with mkfs.xfs -l size=64m (or even 128m) and mount them with noatime,nodiratime,logbufs=8. Xfs file systems also tend to perform better if the journal is placed on a partition of its own. |
Hello and thanks for reply, i am not worried about deletions times but good read then write speed would be nice.
I have amd64 3700mhz with 2gb ram soon to be 4gb so system spec is not an issue. The IBM guide i refer to is at www.ibm.com/developerworks/library/l-fs10.html I normally use following to create xfs FS, setting agcount= as per partition size. Quote:
Which as you can see already uses logbuffer setting but i can up amount as you suggest for logbuffers but i am still not sure about agcount= setting, how many for a 650gb partition? Also can speed be improve but using other xfs settings such as block size? cheers |
http://everything2.com/index.pl?node_id=1479435
Maybe you should use something like Bonnie to find out what works best for you. |
All times are GMT -5. The time now is 04:12 AM. |