Date: Sun, 26 Jun 2011 04:17:11 -0400 From: Robert Simmons <rsimmons0@gmail.com> To: freebsd-questions@freebsd.org Subject: Re: Performance of a USB ZIL for ZFS Message-ID: <201106260417.11482.rsimmons0@gmail.com> In-Reply-To: <20110626074141.GB44024@dan.emsphone.com> References: <4E06180F.7090409@gmail.com> <4E06C2D1.4050601@gmail.com> <20110626074141.GB44024@dan.emsphone.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 25 Jun 2011, at 19:17, Joshua Isom<jrisom@gmail.com> wrote: > I was wondering if anyone had tried using a decent USB flash drive for > the ZIL. I know it'd be hard finding one fast enough, but some from > patriot seem like they might be suitable for home use. Part of the > idea is to just minimize hard drive thrashing and the wear and tear > associated with it. If it helps prevent the drives from going bad, > and doesn't hurt performance too bad all the better. But if it's > going to hurt performance too much or not help prevent thrashing > there isn't a point. You question is a good one, but I think the reason for your question may be off. If you want the ZIL in a separate location it is to cut down on latency rather than "thrashing". See: http://www.solarisinternals.com/wiki/index.php/ZFS_Evil_Tuning_Guide#Disabling_the_ZIL_.28Don.27t.29 If your concern really really is "thrashing" please consider the cost of flash memory vs a hard drive. Replacing a bad hard drive is cheaper. After a cursory glance at newegg, you can see the price per MB for: HDD $0.09 USB flash $0.64 SSD $1.875
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201106260417.11482.rsimmons0>