On Fri, Jul 29, 2011, Mattieu Baptiste wrote: > After digging around this problem with help from Pedro, I noticed that > a 4.9-release kernel works ok, whereas a 5.0-beta does not. So I tried > to identify which commit was responsible and found out this one is > responsible of *very* slow writes with softdep (I only have this bug > on sparc64): > http://marc.info/?l=openbsd-cvs&m=130730313107059&w=2 > > I can add that this bug is just affecting softdep: > - dd'ing to the raw device is fast, > - dd'ing to the file system mounted sync is very fast, > - dd'ing to the file system mounted async is very fast, > - dd'ing to the file system mounted with softdep is very slow. > > I can also add that changing a working kernel to bufcachepercent >=42 > via sysctl is ok too.
What happens if you change bufcachepercent to a much smaller value, like the 4.9 default?
