Date: Mon, 19 Jun 2017 23:24:49 +0100 From: Steven Hartland <killing@multiplay.co.uk> To: freebsd-fs@freebsd.org Subject: Re: FreeBSD 11.1 Beta 2 ZFS performance degradation on SSDs Message-ID: <27c6a211-e2d6-2f40-6bb0-469ce7a42bb6@multiplay.co.uk> In-Reply-To: <a5d5c979ef6e4889b619cfc626b59004@DM2PR58MB013.032d.mgd.msft.net> References: <a5d5c979ef6e4889b619cfc626b59004@DM2PR58MB013.032d.mgd.msft.net>
next in thread | previous in thread | raw e-mail | index | archive | help
vfs.zfs.min_auto_ashift is a sysctl only its not a tuneable, so setting i= t in /boot/loader.conf won't have any effect. There's no need for it to be a tuneable as it only effects vdevs when the= y are created, which an only be done once the system is running. You don't explain why you believe there is degrading performance? What is the exact dd command your running as that can have a huge impact = on performance. On 19/06/2017 23:14, Caza, Aaron wrote: > I've been having a problem with FreeBSD ZFS SSD performance inexplicab= ly degrading after < 24 hours uptime as described in a separate e-mail t= hread. In an effort to get down to basics, I've now performed a ZFS-on-R= oot install of FreeBSD 11.1 Beta 2 amd64 using the default Auto(ZFS) inst= all using the default 4k sector emulation (vfs.zfs.min_auto_ashift=3D12) = setting (no swap, not encrypted). > > Firstly, the vfs.zfs.min_auto_ashift=3D12 is set correctly in the /boot= /loader.conf file, but doesn't appear to work because when I log in and d= o "systctl -a | grep min_auto_ashift" it's set to 9 and not 12 as expecte= d. I tried setting it to vfs.zfs.min_auto_ashift=3D"12" in /boot/loader.= conf but that didn't make any difference so I finally just added it to /e= tc/sysctl.conf where it seems to work. So, something needs to be changed= to make this functionaly work correctly. > > Next, after reboot I was expecting somewhere in the neighborhood of 950= MB/s from the ZFS mirrored zpool of 2 Samsung 850 Pro 256GB SSDs that I'm= using as I was previously seeing this before with my previous FreeBSD 11= -Stable setup which, admittedly, is a different from the way the bsdinsta= ll script does it. However, I'm seeing half that on bootup. > > Performance result: > Starting 'dd' test of large file...please wait > 16000+0 records in > 16000+0 records out > 16777216000 bytes transferred in 37.407043 secs (448504207 bytes/sec) > > Zpool Status: > pool: zroot > state: ONLINE > scan: none requested > config: > > NAME STATE READ WRITE CKSUM > zroot ONLINE 0 0 0 > mirror-0 ONLINE 0 0 0 > ada0p2 ONLINE 0 0 0 > ada1p2 ONLINE 0 0 0 > > /boot/loader.conf: > kern.geom.label.disk_ident.enable=3D"0" > kern.geom.label.gptid.enable=3D"0" > vfs.zfs.min_auto_ashift=3D12 > vfs.zfs.arc_min=3D"50M" > vfs.zfs.arc_max=3D"51M" > zfs_load=3D"YES" > > /etc/sysctl.conf: > vfs.zfs.min_auto_ashift=3D12 > > > Is this the expected behavior now in FreeBSD 11.1? > > -- > Aaron > This message may contain confidential and privileged information. If it= has been sent to you in error, please reply to advise the sender of the = error and then immediately delete it. If you are not the intended recipie= nt, do not read, copy, disclose or otherwise use this message. The sender= disclaims any liability for such unauthorized use. PLEASE NOTE that all = incoming e-mails sent to Weatherford e-mail accounts will be archived and= may be scanned by us and/or by external service providers to detect and = prevent threats to our systems, investigate illegal or inappropriate beha= vior, and/or eliminate unsolicited promotional e-mails (spam). This proce= ss could result in deletion of a legitimate e-mail before it is read by i= ts intended recipient at our organization. Moreover, based on the scannin= g results, the full text of e-mails and attachments may be made available= to Weatherford security and other personnel for review and appropriate a= ction. If you have any concerns about this process, > please contact us at dataprivacy@weatherford.com. > _______________________________________________ > freebsd-fs@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-fs > To unsubscribe, send any mail to "freebsd-fs-unsubscribe@freebsd.org"
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?27c6a211-e2d6-2f40-6bb0-469ce7a42bb6>