Re: {* 05.00 *}Re: Re: Re: Desperate with 870 QVO and ZFS
[email protected] Thu, 07 Apr 2022 16:01:04 +0200
| Newsgroups | gmane.os.freebsd.devel.hackers,gmane.os.freebsd.devel.file-systems,gmane.os.freebsd.performance |
|---|---|
| Message-ID | <[email protected]> |
--=_74b7e4b05962e4b9793f3fbab21fa2c0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Hi Mike! Thanks a lot for your answer :) :) and your time :) :) Answering below in blue bold... El 2022-04-07 13:25, mike tancsa escribió: > On 4/7/2022 4:59 AM, [email protected] wrote: > >> > Hi, > > With respect to compression, I think there is a sweet spot somewhere, where compression makes things faster if your disk IO is the limiting factor and you have spare CPU capacity. I have a separate 13.x zfs server with ztsd enabled and I get compression rations of 15:1 as it stores a lot of giant JSON txt files. > > ZTSD OR ZTSD-2 AS IN SOME MAIL PREVIOUS STEFAN STATED?. I ASSUME ARE NOT THE SAME... ARE THEY?. > > Think of the extreme case where you do something like > > dd if=/dev/zero of=/tank/junk.bin bs=1m count=10000 > > as this is a 20G file that takes just a few hundred bytes of write IO on a compressed system. Obviously, as the compress ratio reduces in the real world the benefits become less. Where that diminishing return is, not sure. But something to keep in mind > > TOTALLY TRUE AND TOTALLY AGREE MIKE!! > CHEERS!! --=_74b7e4b05962e4b9793f3fbab21fa2c0 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=UTF-8 <html><head><meta http-equiv=3D"Content-Type" content=3D"text/html; charset= =3DUTF-8" /></head><body style=3D'font-size: 10pt; font-family: Verdana,Gen= eva,sans-serif'> <p>Hi Mike!</p> <p><br /></p> <p>Thanks a lot for your answer :) :) and your time :) :)</p> <p><br /></p> <p>Answering below in blue bold...</p> <div> </div> <p><br /></p> <p>El 2022-04-07 13:25, mike tancsa escribió:</p> <blockquote type=3D"cite" style=3D"padding: 0 0.4em; border-left: #1010ff 2= px solid; margin: 0"><!-- html ignored --><!-- head ignored --><!-- meta ig= nored --> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= <br /> <span style=3D"white-space: nowrap;">On 4/7/2022 4:59 = ;AM, <a href=3D"mailto:[email protected]">[email protected]</a>&= nbsp;wrote:</span> <blockquote type=3D"cite" style=3D"padding: 0 0.4em; border-left: #1010ff 2= px solid; margin: 0"><br /><span style=3D"white-space: nowrap;"></span></bl= ockquote> <span style=3D"white-space: nowrap;">Hi,</span><br /> <br /> &n= bsp; With respect to compression, I think there is a sweet spot somewhere, = where compression makes things faster if your disk IO is the limiting facto= r and you have spare CPU capacity. I have a separate 13.x zfs server = with ztsd enabled and I get compression rations of 15:1 as it stores a lot = of giant JSON txt files.</div> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= </div> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= <strong><span style=3D"color: #0000ff;">ztsd or ztsd-2 as in some mail prev= ious Stefan stated?. I assume are not the same... are they?.</span></strong= ><br /> <br /> <span style=3D"white-space: nowrap;">Think of the&= nbsp;extreme case where you do something like= </span><br /> <br /> <span style=3D"white-space: nowrap;">dd if=3D/dev= /zero of=3D/tank/junk.bin bs=3D1m count=3D10000</span></div> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= </div> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= as this is a 20G file that takes just a few hundred bytes of write IO on a = compressed system. Obviously, as the compress ratio reduces in the real wor= ld the benefits become less. Where that diminishing return is, not su= re. But something to keep in mind</div> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= </div> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= <strong><span style=3D"color: #0000ff;">Totally true and totally agree Mike= !!</span></strong></div> <div class=3D"pre" style=3D"margin: 0; padding: 0; font-family: monospace">= </div> <strong><span style=3D"color: #0000ff;">Cheers!!</span></strong></blockquot= e> </body></html> --=_74b7e4b05962e4b9793f3fbab21fa2c0--