On Tue, Sep 8, 2015 at 3:12 PM, Gregory Farnum <gfarnum@xxxxxxxxxx> wrote: > On Tue, Sep 8, 2015 at 3:06 PM, Haomai Wang <haomaiwang@xxxxxxxxx> wrote: >> Hit "Send" by accident for previous mail. :-( >> >> some points about pglog: >> 1. short-alive but frequency(HIGH) > > Is this really true? The default length of the log is 1000 entries, > and most OSDs have ~100 PGs, so on a hard drive running at 80 > writes/second that's about 100000 seconds (~27 hours) before we delete > an entry. In reality most deployments aren't writing that > quickly....and if something goes wrong with the PG we increase to > 10000 log entries! > -Greg Er, whoops, as Ilya points out I've left out a step here. 100000 entries at 80 entries/sec is only 1250 seconds, or about 20 minutes. That's quite a different number and you should perhaps just ignore me. :) -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
