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Re: Testing 7.0 Beta: FFS still very slow when creating files



   Date: Mon, 25 Aug 2014 20:02:44 +0200
   From: "J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>

   Short answer: it is -- reverting external/gpl3/gcc/dist/gcc/builtins.c
   from Rev. 1.3 to 1.2 brings back the old times which are the same as
   they were on NetBSD 6.

   Given that this test has many calls to ufs_lookup/cache_lookup using
   memcmp to check for equal filenames this is not a surprise.

   A rather naive "implementation" of memcmp (see below) drops the running
   time from ~15 sec to ~9 secs.  We should consider improving our memcmp.

Sounds reasonable to me, although it looks like GCC's old builtin
memcmp expansion actually failed to implement our specification: it
returns -1, 0, or +1, like your patch, rather than the difference of
the first differing bytes or zero as our man page specifies.  For most
uses it doesn't matter, of course, but we ought to make sure to follow
our own specification.


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