Re: disk performance benchmarks

>You can see there's not much progress being made there.   In the
>presence of a farily pathetic writeout, there's a tiny trickle of disk
>reads, userspace isn't making any progress, the kernel isn't busy, and
>few processes are in iowait.  So what the heck is going on?
>
>This state of non-progress persists as long as the checkpoint subprocess
>is active.  I'm sure there's some magic way to improve this but I
>haven't found it yet.
>
>  
>
Hello,

It is my experience that RAID 5 is not that great for heavy write 
situations and that RAID 10 is better.
Also as you are on linux you may want to take a look at what file system 
you are using. EXT3 for example is
known to be stable, if a very slow piggy.

J





>PS this is with Linux 2.6.7.
>
>Regards,
>jwb
>
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