Re: building initramfs is slow

[John Reiser <jreiser-Po6cBsTGB2ZWk0Htik3J/w@public.gmane.org>]

On 08/18/2011 11:25 AM, Harald Hoyer wrote:
> Try dracut version 013. It's already faster.

Yes, there is some improvement, but I still seek a *factor* of 3 to 4
overall before cpio+gzip.  All the slow coding persists.


$ time /abs/path/to/dracut-013/dracut --local --force test2.img
###  [fixed-width font, please]   contrast to dracut-011
   real  59s                           +3s
   user  26s                           +6s
   sys   29s                           -2s

     26.0MB  output image            + 11.1MB
     69.0MB  unzipped                + 28.0MB
   1947      files listed by cpio    +328  files
    483      .ko kernel modules      +116  modules

## Note the results have gotten larger (time, bytes, files, modules).
## The input (and configuration) has evolved, too.


$ strace -o strace.out -f -e trace=execve /abs/path/to/dracut-013/dracut --local --force test2.img
  11349  SIGCHLD                    -1169  processes   !yea!
   7544  execve                     -1373  execve      !yea!
   3805  fork-and-no-exec           + 214  shell builtins that get a process


   2686 execve("/bin/egrep"         -1117  good, but should be at most a few dozen
   1587 execve("/bin/cp"            + 244
    491 execve("/sbin/modinfo"      + 116
    468 execve("/bin/chmod"         + 109
    458 execve("/bin/rm"
    455 execve("/sbin/modprobe"
    320 execve("/bin/readlink"
    318 execve("/bin/mkdir"
    285 execve("/lib64/ld-linux..."  -573  !yea!
    166 execve("/usr/bin/ldd"        -594  !yea!
    119 execve("/bin/cat"
     88 execve("/bin/ln"
     44 execve("/bin/grep"
     17 execve("/bin/find"

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