Date: Mon, 01 Sep 2008 17:21:59 +0200 From: Arnaud Houdelette <arnaud.houdelette@tzim.net> To: John Birrell <jb@what-creek.com> Cc: stable@freebsd.org Subject: Re: Re: ZFS performance issues (solved?!) Message-ID: <48BC0897.8030602@tzim.net> In-Reply-To: <alpine.BSF.1.10.0809010539210.52681@ibyngvyr.purzvxnyf.bet> References: <20080901021528.GB56694@what-creek.com> <alpine.BSF.1.10.0809010539210.52681@ibyngvyr.purzvxnyf.bet>
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Wes Morgan a écrit : > <div class="moz-text-flowed" style="font-family: -moz-fixed">On Mon, 1 > Sep 2008, John Birrell wrote: > >> For those people experiencing a performance degradation since the >> DTrace import, please update your copy of >> src/sys/cddl/compat/opensolaris/kern/opensolaris_kmem.c by either >> cvsup of direct edit to remove "#define KMEM_DEBUG". >> >> You only need to rebuild the opensolaris kernel module after this >> change. The code is shared between ZFS and DTrace via the opensolaris >> kernel module. >> >> This is also the reason why you found it necessary to add KDB, DDB >> and STACK to your kernel. After removing KMEM_DEBUG, you won't need >> those. >> >> Please confirm that this solves the problem you have been seeing. > > 8 or so hours later and everything is good here. > > One other suggestion, the "opensolaris" module that is now required > for zfs is not mentioned anywhere in UPDATING. Users of > "MODULES_OVERRIDE" will likely find themselves with a system that will > not boot without manual intervention, sometimes even requiring a live > cd. A headsup or warning would probably be appreciated by other zfs'ers. I had really bad performance before removing the line. I had to disable zil on zfs (my /usr/src is on zfs) to be able to recompile, as one of the zil process was eating up nearly all off the CPU. After rebuild/install kernel, no problems anymore. Thanks. I second the above suggestion about opensolaris. There's no mention anywhere of this module (or at least, I didn'it find one before), on UPDATING nor on the list of what this module is for ?
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