Re: [Monotone-devel] Speedup chances

[Eric Anderson]

Jack Lloyd writes:
 > On Fri, May 02, 2008 at 09:05:06PM +0200, Christof Petig wrote:
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 > > 
 > > just some notes for myself on the performance problems with OE:
 > > 
 > > - - hex_decode is used extensively by roster.cc: parse_marking (and
 > > expensive)
 > > - - get_roster_version is taking 90% of the time
 > > - - hex_decode is taking 25% of the time
 > > - - hex_encode is taking 15% of the time (both use malloc extensively)
 > > 
 > > Most probably a hand coded hex decoder for a fixed length of 40 digits
 > > would not take 10000 cycles per call 8-O
 > 
 > [ want faster hex encode/decode ]

Revision acbe5243f51aa69674dc1cd8675a49835bfca8db includes a fix to
transforms.{cc,hh} to have a fast string -> string hex encoder.  If
you had a fast enough hash function, avoiding the malloc call to build
a string could help, but it would take careful measurement to verify
that it is fast enough.  (I'd tend to bet against unless the malloc
implementation is really slow)
        -Eric