Date: Tue, 18 Sep 2007 22:43:10 -0400 (EDT) From: Garrett Wollman <wollman@hergotha.csail.mit.edu> To: FreeBSD-gnats-submit@FreeBSD.org Subject: bin/116452: pkg_create uses bogosort? Message-ID: <200709190243.l8J2hAl0041538@hergotha.csail.mit.edu> Resent-Message-ID: <200709190250.l8J2o1lH004218@freefall.freebsd.org>
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>Number: 116452
>Category: bin
>Synopsis: pkg_create uses bogosort?
>Confidential: no
>Severity: non-critical
>Priority: high
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Wed Sep 19 02:50:01 GMT 2007
>Closed-Date:
>Last-Modified:
>Originator: Garrett Wollman
>Release: FreeBSD 6.2-RELEASE-p3 i386
>Organization:
>Environment:
System: FreeBSD hergotha.csail.mit.edu 6.2-RELEASE-p3 FreeBSD 6.2-RELEASE-p3 #5: Sun Mar 18 00:59:50 EDT 2007 wollman@hergotha.csail.mit.edu:/usr/obj/usr/src/sys/HERGOTHA i386
>Description:
pkg_create makes an insane number of pointless filesystem
operations (quadratic? exponential?) when being run as part of
the "Registering installation" step of a port install.
It is definitely a function of the number of ports installed,
as it has gotten much worse since X was fragmented into 200
separate packages. ktrace shows:
[root@hergotha /home/wollman]# kdump -t n | wc -l
937814
[root@hergotha /home/wollman]# kdump -t n | sort -u | wc -l
1023
(This is actually only a partial ktrace, started about halfway
through the process.) What it is actually trying to do, I do
not know. A representative sample from the trace:
97936 pkg_create CALL lstat(0xbfbfbe20,0xbfbfb990)
97936 pkg_create NAMI "/var/db/pkg/glitz-0.5.6_1"
97936 pkg_create RET lstat 0
97936 pkg_create CALL access(0xbfbfbe20,0x4)
97936 pkg_create NAMI "/var/db/pkg/glitz-0.5.6_1"
97936 pkg_create RET access 0
97936 pkg_create CALL stat(0xbfbfba20,0xbfbfb990)
97936 pkg_create NAMI "/var/db/pkg/glitz-0.5.6_1/+CONTENTS"
97936 pkg_create RET stat 0
97936 pkg_create CALL access(0xbfbfba20,0x4)
97936 pkg_create NAMI "/var/db/pkg/glitz-0.5.6_1/+CONTENTS"
97936 pkg_create RET access 0
>How-To-Repeat:
Install an already-compiled port on a machine that has lots of
packages. Wait a few minutes. Wonder why it's not done yet.
>Fix:
Either use a less-stupid algorithm or at least memoize the
result of whatever it's trying to do with this sequence of
calls.
>Release-Note:
>Audit-Trail:
>Unformatted:
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