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<!DOCTYPE bugzilla SYSTEM "https://bugzilla.yoctoproject.org/page.cgi?id=bugzilla.dtd">

<bugzilla version="5.0.6"
          urlbase="https://bugzilla.yoctoproject.org/"
          
          maintainer="it-coreprojects-helpdesk@linuxfoundation.org"
>

    <bug>
          <bug_id>4377</bug_id>
          
          <creation_ts>2013-04-22 12:32:36 +0000</creation_ts>
          <short_desc>[Performance] The switch to turn off the generation of .sigdata file</short_desc>
          <delta_ts>2013-05-24 13:19:16 +0000</delta_ts>
          <reporter_accessible>1</reporter_accessible>
          <cclist_accessible>1</cclist_accessible>
          <classification_id>7</classification_id>
          <classification>Build System, Metadata &amp; Runtime</classification>
          <product>BitBake</product>
          <component>bitbake</component>
          <version>1.5</version>
          <rep_platform>x86</rep_platform>
          <op_sys>Multiple</op_sys>
          <bug_status>VERIFIED</bug_status>
          <resolution>WONTFIX</resolution>
          
          
          <bug_file_loc></bug_file_loc>
          <status_whiteboard></status_whiteboard>
          <keywords></keywords>
          <priority>Medium</priority>
          <bug_severity>enhancement</bug_severity>
          <target_milestone>1.5 M3</target_milestone>
          
          
          <everconfirmed>1</everconfirmed>
          <reporter name="Robert Yang">liezhi.yang</reporter>
          <assigned_to name="Robert Yang">liezhi.yang</assigned_to>
          <cc>alexandru.c.georgescu</cc>
    
    <cc>mark.hatle</cc>
    
    <cc>poky.bs.watcher</cc>
    
    <cc>poky.watcher</cc>
    
    <cc>richard.purdie</cc>
    
    <cc>sgw</cc>
          
          
          <cf_os>---</cf_os>
          <cf_regression_type>---</cf_regression_type>
          
          <cf_docchange>---</cf_docchange>

      

      

      

          <comment_sort_order>oldest_to_newest</comment_sort_order>  
          <long_desc isprivate="0" >
    <commentid>32447</commentid>
    <comment_count>0</comment_count>
    <who name="Robert Yang">liezhi.yang</who>
    <bug_when>2013-04-22 12:32:36 +0000</bug_when>
    <thetext>The .sigdata file isn&apos;t usually used by the end user, we can generate it by default, but it would be good if we have a switch for it, for example, BB_NO_SIGDATA, this would not save much disk space (only about 120M for a core-image-sato build), but it would save a mount of disk I/O, when many people (or multi builds) works on the same sever, the disk I/O is usually the bottleneck, the build would cost much time on I/O waiting, reduce the disk I/O would save time.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>32449</commentid>
    <comment_count>1</comment_count>
    <who name="Richard Purdie">richard.purdie</who>
    <bug_when>2013-04-22 12:45:41 +0000</bug_when>
    <thetext>The sigdata files are there to allow for debugging of the system. Whilst they may not be commonly used, they are invaluable in trying to debug what went into a given checksum and what might have changed.

I seriously doubt these have much impact on overall build time. I&apos;d want to see statistics proving this was some kind of build bottleneck before any such patch was taken.

Please feel free to provide supportive evidence of this being a problem but right now I&apos;m not convinced it is (quite the opposite) so I&apos;m marking the bug accordingly.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>32450</commentid>
    <comment_count>2</comment_count>
    <who name="Richard Purdie">richard.purdie</who>
    <bug_when>2013-04-22 12:46:39 +0000</bug_when>
    <thetext>As an aside, if I/O is a worry, we could compress them. Again, I&apos;d like to see numbers showing this is a real problem first though.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>32508</commentid>
    <comment_count>3</comment_count>
    <who name="Robert Yang">liezhi.yang</who>
    <bug_when>2013-04-23 08:21:19 +0000</bug_when>
    <thetext>(In reply to comment #2)
&gt; As an aside, if I/O is a worry, we could compress them. Again, I&apos;d like to
&gt; see numbers showing this is a real problem first though.

Hi RP, I&apos;ve done several builds without the generation of .sigdata and python&apos;s temp/run.*, but it doesn&apos;t make much difference, only about 40 seconds saved for a core-image-sato build (the host&apos;s load is not high, the whole builds cost 156m53.460s), so drop this one is the right way.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>33287</commentid>
    <comment_count>4</comment_count>
    <who name="Alexandru Georgescu">alexandru.c.georgescu</who>
    <bug_when>2013-05-24 13:19:16 +0000</bug_when>
    <thetext>Verified as per above comments.</thetext>
  </long_desc>
      
      

    </bug>

</bugzilla>