On Tue, Jan 7, 2020 at 4:10 PM Alexander Motin <m...@freebsd.org> wrote:
> Author: mav > Date: Tue Jan 7 23:10:38 2020 > New Revision: 356480 > URL: https://svnweb.freebsd.org/changeset/base/356480 > > Log: > Increate HMB limit from 1% to 5%. > > SSD capacity in laptops is growing faster then RAM size, so my original > guess seems too low on second thought. Hopefully nobody will build large > array of those crappy SSDs. > If they do, they will likely want to turn off host buffer support anyway, since it uses PCIe bandwidth and large arrays tend to oversubscribe the PCIe bus... Warner > MFC after: 2 weeks > X-MFC-with: 356474 > > Modified: > head/sys/dev/nvme/nvme_ctrlr.c > > Modified: head/sys/dev/nvme/nvme_ctrlr.c > > ============================================================================== > --- head/sys/dev/nvme/nvme_ctrlr.c Tue Jan 7 22:45:02 2020 > (r356479) > +++ head/sys/dev/nvme/nvme_ctrlr.c Tue Jan 7 23:10:38 2020 > (r356480) > @@ -881,8 +881,8 @@ nvme_ctrlr_hmb_alloc(struct nvme_controller *ctrlr) > int err, i; > uint64_t max; > > - /* Limit HMB to 1% of RAM size per device by default. */ > - max = (uint64_t)physmem * PAGE_SIZE / 100; > + /* Limit HMB to 5% of RAM size per device by default. */ > + max = (uint64_t)physmem * PAGE_SIZE / 20; > TUNABLE_UINT64_FETCH("hw.nvme.hmb_max", &max); > > min = (long long unsigned)ctrlr->cdata.hmmin * 4096; > _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
