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Date: Fri, 25 Oct 2013 10:32:19 +0300
From: Vitalij Satanivskij <satan@ukr.net>
To: Steven Hartland <killing@multiplay.co.uk>
Subject: Re: ZFS L2ARC - incorrect size and abnormal system load on r255173
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Cc: Vitalij Satanivskij <satan@ukr.net>, freebsd-current@freebsd.org,
 Dmitriy Makarov <supportme@ukr.net>
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Just after system reboot with this patch 

found 
kstat.zfs.misc.arcstats.l2_compress_successes: 6083
kstat.zfs.misc.arcstats.l2_compress_zeros: 1
kstat.zfs.misc.arcstats.l2_compress_failures: 296

compression on test pool (where I'm test this patch) is lz4 

so is it ok ?



Steven Hartland wrote:
SH> If you are still seeing high load try commenting out the following
SH> which should disable l2arc compression.
SH> sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
SH>         if (l2arc_compress)
SH>                 hdr->b_flags |= ARC_L2COMPRESS;
SH>