On Wed, 2011-05-04 at 03:57 +0530, Rahul Sundaram wrote: > On 05/03/2011 11:47 PM, David Malcolm wrote: > > I'm also working on this Fedora 16 idea, which should help both PyPy and > > CPython more robust: > > http://fedoraproject.org/wiki/Features/StaticAnalysisOfCPythonExtensions > > though it's early days yet, and I don't yet know how good the > > signal:noise ratio for the tool will be, which will affect how tightly > > we will want to integrate this into Fedora's build system. (I'm about > > to go on vacation, and I don't want to open up the code until I get > > back, later this month). > > > > Hope this all sounds sane > > Yes indeed and thanks for the info. http://speed.pypy.org/ looks very > impressive and with the tradeoff of less debugability, I wasn't sure > how much it impacts the speed of say yum. Have you had a chance to look > at that? I haven't specifically looked at yum yet, but yum is heavily enmeshed with the rpm python bindings, which are largely in C Note that PyPy has to do extra work for C extension modules: the PyObject* it provides are all just wrappers around PyPy's "real" objects, so there is a CPU cost at the python/C boundary that isn't present in CPython. This, and the fact that the C code is invisible to the JIT compiler means that a workload that's calling into C extension code a lot might not gain much from the JIT compiler. (Optimization advice for PyPy is often to recode C back into Python, since pure Python code is amenable to optimizations when being JIT-compiled). So additional work may be needed to support pypy running yum and to get speed and memory usage improvements, and I don't know if it would be worth it. So far, every time I've tried to use PyPy's C extension support, the extension has either not built, or it's segfaulted on me very quickly. This was with 1.4 and 1.4.1 though, and a lot of work was done in 1.5 on this area. If you want to play with this, you could try the pypy-devel rpm, or try building pypy from source, but obviously you'll want to do it on a testing rpm db, not on the rpm db of a machine you care about ;) It's probably only worth doing if you're familiar with gdb, too, and are willing to dive deep into the guts of PyPy, rpm and yum :) I may have a chance to do this when I get back from vacation. Dave -- test mailing list test@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe: https://admin.fedoraproject.org/mailman/listinfo/test
