On 01.08.2010 11:47, Mattias Gaertner wrote:
the OS file cache
The OS cache already does a great Job:
r...@t40:/home/bernd\ $ sync && echo 3 > /proc/sys/vm/drop_caches
be...@t40:~/lazsvn/lazarus/trunk\ $ time make ide
[...]
real 1m12.491s
user 0m8.653s
sys 0m2.348s
be...@t40:~/lazsvn/lazarus/trunk\ $ time make ide
[...]
real 0m6.127s
user 0m4.752s
sys 0m0.916s
1:12 with a cold cache versus 0:06 when the cache is warm is an
impressive difference.
There exists a small tool for linux that tries to speed up file access
with an extremely pragmatic but very effective approach by simply
permanently monitoring which files are usually read most often by all
the user's applications and then as a daemon running on idle priority
permanently read all those files in intervals of a few minutes which
will ensure that they are always all in the OS file cache.
Lazarus could adopt this idea and could after opening a project during
idle time and in reasonable intervals read every file that would also be
read by the compiler and linker. Maybe in a certain order that makes
sense: first only the directory listings to immediately have all file
timestamps, then all compiled units that would be needed (because most
source will not have changed since it was compiled the last time) and
then after this is done read all source files belonging to the project.
--
_______________________________________________
Lazarus mailing list
[email protected]
http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
