I currently am getting good speeds out of my existing system (8x 2TB in a
RAIDZ2 exported over fibre channel) but there's no such thing as too much
speed, and these other two drive bays are just begging for drives in
them.... If I go to 10x 2TB in a RAIDZ3, will the extra spindles increase
speed, or will the extra parity writes reduce speed, or will the two factors
offset and leave things a wash?
(My goal is to be able to survive one controller failure, so if I add
more drives I'll have to add redundancy to compensate for the fact that one
controller would then be able to take out three drives.)
I've considered adding a drive for the ZIL instead, but my experiments
in disabling the ZIL (using the evil tuning guide at
<http://www.solarisinternals.com/wiki/index.php/ZFS_Evil_Tuning_Guide#Disabl
ing_the_ZIL_.28Don.27t.29>) didn't show any speed increase. (I know it's a
bad idea run the system with ZIL disabled; I disabled it only to measure its
impact on my write speeds and re-enabled it after testing was complete.)
Current system:
OpenSolaris dev release b132
Intel S5500BC mainboard (latest firmware)
Intel E5506 Xeon 2.13GHz
8GB RAM
3x LSI 3018 PCIe SATA controllers (latest IT firmware)
8x 2TB Hitachi 7200RPM SATA drives (2 connected to each LSI and 2 to
motherboard SATA ports)
2x 60GB Imation M-class SSD (boot mirror)
Qlogic 2440 PCIe Fibre Channel HBA
--
Dave Pooser, ACSA
Manager of Information Services
Alford Media http://www.alfordmedia.com
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
