From: David Bremner <david@tethera.net>
Date: Sat, 26 Oct 2013 00:13:45 +0000 (+2100)
Subject: Re: [PATCH v2] new: Don't scan unchanged directories with no sub-directories
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=5d1d22b8e535d1c56ed06fd6c450639893ef49c0;p=notmuch-archives.git

Re: [PATCH v2] new: Don't scan unchanged directories with no sub-directories
---

diff --git a/4f/547c4ca37b06ae87e4a8c320e74f957cd5d30b b/4f/547c4ca37b06ae87e4a8c320e74f957cd5d30b
new file mode 100644
index 000000000..4bd0637f1
--- /dev/null
+++ b/4f/547c4ca37b06ae87e4a8c320e74f957cd5d30b
@@ -0,0 +1,76 @@
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+From: David Bremner <david@tethera.net>
+To: Austin Clements <amdragon@MIT.EDU>, notmuch@notmuchmail.org
+Subject: Re: [PATCH v2] new: Don't scan unchanged directories with no
+	sub-directories
+In-Reply-To: <1382650739-12438-1-git-send-email-amdragon@mit.edu>
+References: <20131024210837.GH20337@mit.edu>
+	<1382650739-12438-1-git-send-email-amdragon@mit.edu>
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+Date: Fri, 25 Oct 2013 21:13:45 -0300
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+
+Austin Clements <amdragon@MIT.EDU> writes:
+
+> This can substantially reduce the cost of notmuch new in some
+> situations, such as when the file system cache is cold or when the
+> Maildir is on NFS.
+
+On my desktop at home (a core i7 950) with spinning rust disks (and lvm
+on luks) this patch yields about a 7% slowdown in the intial new perf
+test
+
+from
+
+			Wall(s)	Usr(s)	Sys(s)	Res(K)	In/Out(512B)
+  Initial notmuch new   579.60	348.86	14.26	217188	5330266/3501272
+
+to
+
+			Wall(s)	Usr(s)	Sys(s)	Res(K)	In/Out(512B)
+  Initial notmuch new   620.51	368.62	15.48	217156	5330354/3416456
+
+On an SSD I don't detect a significant different (<0.5% speedup)
+
+d