On Tue, Mar 08, 2016 at 10:34:23AM -0800, Scott Long wrote: > > > On Mar 8, 2016, at 10:07 AM, Slawa Olhovchenkov <s...@zxy.spb.ru> wrote: > > > > On Mon, Mar 07, 2016 at 02:10:12PM +0300, Slawa Olhovchenkov wrote: > > > >>>>>> This allocated one for all controllers, or allocated for every > >>>>>> controller? > >>>>> > >>>>> It’s per-controller. > >>>>> > >>>>> I’ve thought about making the tuning be dynamic at runtime. I > >>>>> implemented similar dynamic tuning for other drivers, but it seemed > >>>>> overly complex for low benefit. Implementing it for this driver > >>>>> would be possible but require some significant code changes. > >>>> > >>>> What cause of chain_free+io_cmds_active << max_chains? > >>>> One cmd can use many chains? > >>> > >>> Yes. A request uses and active command, and depending on the size of the > >>> I/O, > >>> it might use several chain frames. > > > > I am play with max_chains and like significant cost of handling > > max_chains: with 8192 system resonded badly vs 2048. Now try 3192, > > response like with 2048. > > Hi, I’m not sure I understand what you’re saying. You said that you tried > 8192, but the system still complained of being out of chain frames? Now you > are trying fewer, only 3192?
With 8192 system not complained of being out of chain frames, but like need more CPU power to handle this chain list -- traffic graf (this host servered HTTP by nginx) have many "jerking", with 3192 traffic graf is more smooth. _______________________________________________ freebsd-stable@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
