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Markus Schulz wrote:
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<pre wrap="">Am Donnerstag, 14. Februar 2008 schrieb John Drescher:
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<pre wrap="">On Thu, Feb 14, 2008 at 9:49 AM, Mark Hutchinson <a class="moz-txt-link-rfc2396E" href="mailto:mark@onnow.net"><mark@onnow.net></a>
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<pre wrap=""><!---->wrote:
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<pre wrap="">I have read a bunch of docs, but wanted to get some feedback or
reports of results.
HD system. firewire capture etc.... 3ghz Core2Duo, 5 sata ports.
I have 5-500gig sata drives for storage.
LVM would work, but provide no RAID. RAID 5 is too slow from what
I have read.
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<pre wrap="">With a modern CPU write speeds are > single disk speed but things
slow down when you have a lot of thrashing. Read speeds are nearly
RAID 0 for N-1 disks. I get 266MB/s hdparm reads on a 6 drive
software raid 6 (AM2 Althlon 3000 single core + 2GB PC6400 DDR2 + 6 X
320 Segate 7200.10) and 90MB/s writes.
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raid5/6 has the problem that for each write he must read from all other
disk to generate the new hash values.
Best write performance with redundancy you will get by RAID10.
At work i've build a pgsql-maschine with 6 73GB SAS 15k disks RAID10 and
got 320MB/s read _and_ write. A RAID5/6 don't get much more write speed
then the write speed of a single disk.
But i think for a mythtv storage write performance from raid5/6 will be
enough and the better solution compared to diskspace-loss from raid10.
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Well the fastest RAID is RAID0, except one bad hard drive and
everything is lost. With RAID10 he'll loose too much disk space. With
5x500G disk, he'll have a 1TB raid partition with one spare I guess
(depends how you use the 5th disk). With Raid 5, the more disk you have
the better the performance and he'll have 2TB of space with some fault
protection.<br>
<br>
Protection, speed, space, pick any 2. RAID5 is the closest thing to all
3.<br>
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