[ZODB-Dev] Cache Query (why doesn't RAM usage ever drop?)

[Christian Reis]

On Fri, Oct 25, 2002 at 10:41:42AM -0400, Shane Hathaway wrote:
> discovered that when you allocate a block of at least 128KB (or whatever 
> you set your threshold to be), malloc actually returns a memory-mapped 
> file instead of space from the heap.  I'm not quite sure where the 
> "file" exists :-) but like obmalloc.c says, instead of wasting memory 

It's a mmap() of /dev/null, quite common to avoid the problems with
sbrk(), which generally breaks and wastes PT entries under stress

Take care,
--
Christian Reis, Senior Engineer, Async Open Source, Brazil.
http://async.com.br/~kiko/ | [+55 16] 261 2331 | NMFL