Date: Thu, 12 Mar 2015 13:08:25 -0400 From: Ryan Stone <rysto32@gmail.com> To: Adrian Chadd <adrian@freebsd.org> Cc: FreeBSD Current <freebsd-current@freebsd.org> Subject: Re: [PATCH] Convert the VFS cache lock to an rmlock Message-ID: <CAFMmRNzD30SspUUuNNKP7Y1zHaA2t_DcGBg6qhnK0GvzLGQjXw@mail.gmail.com> In-Reply-To: <CAJ-Vmo=-vbKqLdkJCs%2B9pMrOVysFCx=iAJphMFLFyZNL38M3eQ@mail.gmail.com> References: <CAFMmRNysnUezX9ozGrCpivPCTMYRJtoxm9ijR0yQO03LpXnwBQ@mail.gmail.com> <CAJ-Vmo=-vbKqLdkJCs%2B9pMrOVysFCx=iAJphMFLFyZNL38M3eQ@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Mar 12, 2015 at 12:37 PM, Adrian Chadd <adrian@freebsd.org> wrote: > Do you have access to any boxes that have more than 12 cores? I have a 14-core hyperthreaded machine (so 28 logical cores), but it has no disk (long story). I could do a build out of a memory disk though. Also, to ask a stupid question - why wasn't the reader gifted a > temporary priority boost because you were trying to acquire the write > lock? > rwlocks don't have any metadata tracking what threads hold a read lock, so it's impossible to propagate priority to them. rwlocks only keep a counter of the number of readers.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAFMmRNzD30SspUUuNNKP7Y1zHaA2t_DcGBg6qhnK0GvzLGQjXw>