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From:Derick H Siddoway Date:April 22 1999 10:36pm
Subject:Re: Ballpark performance.
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>Now, I'm curious what sort of HDD subsystem you're using. We're running
>(don't hit me for that) a RAID5 UW SCSI system with 5 HDDs. How much
>performance could I gain setting up a RAID1-0 (striping over mirrors)
>array with 4 HDDs, dedicated for the mysql tree? 


In general, you'll see a small (~25%) increase in read performance,
but a larger (~200%) increase in write performance, for sequential
reads & writes.  For random reads and writes, the increase is less
substantial: ~5% for reads and ~70% for writes.

Big thing to consider, though, is that you'll lose disk space in a
RAID0+1 setup.  Let's assume you have 4 9GB drives.  With RAID5,
you get about 27GB usable, while with RAID0+1, you get only 18GB usable.
Plus, to be safer, you should be running them under some sort of
volume management (more $$) and an extra hot spare (even more $$).

But that cost may be worth it to you.

-- 
derick

Thread
Ballpark performance.Brian Bray22 Apr
  • Re: Ballpark performance.Sasha Pachev22 Apr
  • Re: Ballpark performance.Daniel Koch22 Apr
RE: Ballpark performance.tcobb22 Apr
Re: Ballpark performance.(David Sklar)22 Apr
Re: Ballpark performance.Matthias Pigulla22 Apr
Re: Ballpark performance.(David Sklar)23 Apr
Re: Ballpark performance.Derick H Siddoway23 Apr