topic Re: Optimizing file system in Operating System - HP-UX

Optimizing file system

Mario_88 — Tue, 13 Mar 2007 07:11:21 GMT

Hello:

I am trying to improve the performance of a filesystem. The main process that uses this filesystem writes in the following way:
------------------------
write(32768)
write(229376)
write(32768)
write(229376)
write(32768)
-------------------------
As you can see 256 Kb writes are divided in two physical writes 32768 and 229376.

How can we make this two writes combine in one?

Regards,
Mario.

Re: Optimizing file system

Steven E. Protter — Tue, 13 Mar 2007 08:32:37 GMT

Shalom from Chicago Mario,

Online JFS an add in product can be used to defragment a filesystem, which will improve write performance a small amount.

Beyond that, the only other way I can see to improve performance is to look at the disk layout that underlies the filesystem. For heavy writes, raid 1 or raid 10 will perform better than raid 5.

As far as combining the writes, thats a programming question and you'd have to at least give us a hint as to what language you are using.

SEP

Re: Optimizing file system

Bill Hassell — Tue, 13 Mar 2007 17:08:28 GMT

You can't fix bad code with the operating system. There are some optimizations that take place in the driver and VxFS directory code but that is all running just fine. The programmer needs to rewrite the application.

Re: Optimizing file system

Sunny Jaisinghani — Wed, 14 Mar 2007 00:39:29 GMT

Hi,

Defragmenting the file system with fsadm will improve the performance of your file system.

Regards