Thread: Port Bug Report: Backend lseeks needlessly

Port Bug Report: Backend lseeks needlessly

From
Unprivileged user
Date:
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                        POSTGRESQL BUG REPORT TEMPLATE
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Your name               : Doug Mitchell
Your email address      : doug@mitchcraft.com

Category                : runtime: back-end
Severity                : non-critical

Summary: Backend lseeks needlessly

System Configuration
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  Operating System   : RedHat Linux 6.1

  PostgreSQL version : 6.5.2

  Compiler used      : egcs-2.91.66

Hardware:
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i686-pc-linux-gnu

Versions of other tools:
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Problem Description:
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Had the backend processs simple one-record select
and update queries using index scans and watched
it with strace.

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Test Case:
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Attach to running backend with
strace -p pid
and watch all the lseeks

strace -c -p pid
and count lseeks vs reads and writes



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Solution:
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Probably could be handled in the storage manager,
so at least a slow system call is prevented, but
is should be fixed in the upper layers too.

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