[Bf-committers] PATCH to limit memory usage in sequencer

[Peter Schlaile]

Hello,

I just added a patch to the patch tracker for those, who want to use
blender as an NLA-editor for longer movies then a few seconds.

This patch limits the memory usage in the sequencer by throwing out
the oldest cached ImBufs.

It also implements a generic Mem Cache Limiter framework written in C++
with an additional C interface used by the Imbuf cache limiter.

The upper memory cache limit is hard coded to 32 MB for the moment -
I'll add an userpref entry later.

This patch is needed by those who want to use blender as an NLA
video editor for longer sequences (say 15 minutes e.g. or longer if
someone raises the frame limit.)

The upper memory limit is a _soft_ limit. If the sequence renderer
temporarily needs more memory then it is granted. If you want to
test this the hard way, set the memory limit in the source file
(MEM_CacheLimiterC-Api.cpp) to 1 byte. It should still work - blender
will be very slow - but it should work.

Setting the limit to 0 bytes disables the cache limit completely and
blender will eat memory like popcorn again.

Any suggestions are always welcome!

Greetings,
Peter Schlaile