On Mon, 28 Sep 2009, Richard Connamacher wrote:
I'm planning on using RAIDZ2 if it can keep up with my bandwidth
requirements. So maybe ZFS could be an option after all?
ZFS certainly can be an option. If you are willing to buy Sun
hardware, they have a "try and buy" program which would allow you to
set up a system to evaluate if it will work for you. Otherwise you
can use a high-grade Brand-X server and decent-grade Brand-X JBOD
array to test on.
Sun Sun Storage 7000 series has OpenSolaris and ZFS inside but is
configured and sold as a closed-box NAS. The X4550 server is fitted
with 48 disk drives and is verified to be able to deliver 2.0GB/second
to a network.
By MB do you mean mega*byte*? If so, 550 MB is more than enough for
uncompressed 1080p. If you mean mega*bit*, then that's not enough.
But as you said, you're using a mirrored setup, and RAID-Z should be
faster.
Yes. I mean megabyte. This is a 12-drive StorageTek 2540 with two
4gbit FC links. I am getting a peak of more than one FC link
(550MB/second with a huge file).
A JBOD SAS array would be a much better choice now but these products
had not yet come to market when I ordered my hardware.
This might work for Final Cut editing using QuickTime files. But FX
and color grading using TIFF frames at 130 MB/s would slow your
setup to a crawl. Do you think RAID-Z would help here?
There is no reason why RAID-Z is necessarily faster at sequential
reads than mirrors and in fact mirrors can be faster due to fewer disk
seeks. With mirrors, it is theoretically possible to schedule reads
from all 12 of my disks at once. It is just a matter of the
tunings/options that the ZFS implementors decide to provide.
Here are some iozone measurements (taken June 28th) with different
record sizes running up to a 64GB file size:
KB reclen write rewrite read reread
8388608 64 482097 595557 1851378 1879145
8388608 128 429126 621319 1937128 1944177
8388608 256 428197 646922 1954065 1965570
8388608 512 489692 585971 1593610 1584573
16777216 64 439880 41304 822968 841246
16777216 128 443119 435886 815705 844789
16777216 256 446006 475347 814529 687915
16777216 512 436627 462599 787369 803182
33554432 64 401110 41096 547065 553262
33554432 128 404420 394838 549944 552664
33554432 256 406367 400859 544950 553516
33554432 512 401254 410153 554100 558650
67108864 64 378158 40794 552623 555655
67108864 128 379809 385453 549364 553948
67108864 256 380286 377397 551060 550414
67108864 512 378225 385588 550131 557150
It seems like every time I run the benchmark, the numbers have
improved.
Bob
--
Bob Friesenhahn
bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
