Date: Thu, 23 Feb 2012 16:17:10 -0800 From: Doug Barton <dougb@FreeBSD.org> To: John Baldwin <jhb@freebsd.org> Cc: freebsd-hackers@freebsd.org, "hackers@freebsd.org" <hackers@freebsd.org>, Ivan Voras <ivoras@freebsd.org> Subject: Re: PostgreSQL benchmarks (now with Linux numbers) Message-ID: <4F46D706.1060903@FreeBSD.org> In-Reply-To: <201202230822.16304.jhb@freebsd.org> References: <b1732c99-eec2-4097-ad9c-f58979addf9f@email.android.com> <4F45AB76.5050201@FreeBSD.org> <201202230822.16304.jhb@freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On 02/23/2012 05:22, John Baldwin wrote: > On Wednesday, February 22, 2012 9:59:02 pm Doug Barton wrote: >> On 02/22/2012 01:42, Ivan Voras wrote: >>> The Dragonfly team has recently liberated their VM from the giant lock and there are some interesting benchmarks comparing it to FreeBSD 9 and a > derivative of RedHat Enterprise Linux: >>> >>> http://leaf.dragonflybsd.org/mailarchive/kernel/2011-11/msg00008.html >>> >>> Other developments are described in their release notes: http://www.dragonflybsd.org/release30/ >> >> The 4.5 times improvement by enabling kern.ipc.shm_use_phys is pretty >> notable, what prevents us from enabling that by default? > > It makes all your SYSV SHMs wired. That's fine if you are running a dedicated > server using SYSV SHMs where you want that process to use all the RAM in the > machine (e.g. a pgqsl server). It's not so great for a general purpose load > where you would like an otherwise-idle process using SYSV SHMs to have the SHMs > paged out to swap if other processes on the machine need memory and the box is > under memory pressure. I see, thanks for that explanation. Doug -- It's always a long day; 86400 doesn't fit into a short. Breadth of IT experience, and depth of knowledge in the DNS. Yours for the right price. :) http://SupersetSolutions.com/
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4F46D706.1060903>