Re: [ovirt-users] Good practices
Le 8 août 2017 à 15:24, FERNANDO FREDIANI
<fernando.frediani(a)upx.com> a écrit :
That's something on the way RAID works, regardless what most 'super-ultra'
powerfull hardware controller you may have. RAID 5 or 6 will never have the same write
performance as a RAID 10 o 0 for example. Writeback caches can deal with bursts well but
they have a limit therefore there will always be a penalty compared to what else you could
have.
Hardware RAID5/6 can have better performance with quite common hardware that software
RAID0. I have seen many time on on even old servers that write latency (hitting the cache)
was smaller that read latency that was going directly to the disk. I'm not talking
about 'super-ultra' powerfull hardware. An HP Smart Array P440ar with 2 GB flash
is sell at 560€, public price. Not cheap, but not ultra powerfull.
It's now a matter of identifying the bootle neck, and how much money you can throw at
it.