zippy is the -z command line option to AS. It causes an AOL-designed memory allocator to be used instead of the standard C library malloc.
Properties of zippy are that it has separate heaps for each thread instead of a shared heap, thus avoiding the need to lock when malloc'ing private thread storage, and it uses a different alloc/freelist strategy. The wrappers to choose one vs the other are in thread/memory.c. The zippy allocator is in thread/pool.c Jim > > Ok, I must have missed something, or might have been off of the cluetrain too long, >but what exactly is 'zippy'? I did a google search, but I was getting mostly 'zippy >the pinhead' and other weird stuff! > > Anyone have an URL or explanation? > > thanks, > > --brett > > > On Wed, 17 Oct 2001 09:54:25 -0500 > Rob Mayoff <[EMAIL PROTECTED]> wrote: > > > +---------- On Oct 17, Jim Wilcoxson said: > > > In glancing at the zippy code, it looks like it used a power-of-2 > > > algorithm, so I figured it might cause less heap fragmentation. I > > > think that might be at least some of the problem. Does the standard > > > gnu/linux memory allocator handle fragmentation poorly/well? > > > > I think the standard Linux allocator is dl-malloc, which as I recall has > > pretty good fragmentation properties. > > > > The reason zippy may use more memory is that it keeps a separate pool > > of memory for each thread. This reduces lock contention but means that > > less free memory is shared between threads. > > _________________________________________________________ > Do You Yahoo!? > Get your free @yahoo.com address at http://mail.yahoo.com >
