Re: [Boost-build] Glob and startup times.

From: Vladimir Prus (ghost_at_[hidden])
Date: 2006-09-18 02:55:41

On Monday 18 September 2006 10:02, Rene Rivera wrote:
> An update on the startup time for building from the
> boost-root/Jamfile.v2. I just checked in changes to use the faster BBv1
> algorithm for globing through the headers. 

Thanks!

> Before and after perf: 
>
>   --count--  --gross--    --net--     --each--    --mem--   --each--
>           0      81126          0     0.000000  329241390  329241390
>           0      52970          0     0.000000  318892205  318892205
>
> So a savings of 28 seconds and of 9.9M of allocations (the new algo
> takes about 2 seconds to do the glob). Not that a 53 second startup is
> anything to be proud of :-( This leaves the following top 5 time sinks:
>
>   --count--  --gross--    --net--     --each--    --mem--   --each--
>       42586       9352       7082         0.17   57224878       1343
> regex.split
>       10760      14511       5035         0.47   24564384       2282
> toolset.find-property-subset
>        3176       5841       5029         1.58   38371492      12081
> class_at_property-map.find-replace
>        2316       5983       4123         1.78    9523567       4112
> class_at_property-set.__init__
>         752      17544       1768         2.35   22136926      29437
> toolset.set-target-variables-aux

It looks like 3 of those function are used to set variables on target 
depending on properties. I think we might need to rewrite that part of the 
code in C ;-)

- Volodya

Thanks,
Volodya

-- 
Vladimir Prus
http://vladimir_prus.blogspot.com
Boost.Build V2: http://boost.org/boost-build2