[Python-Dev] bsddb3 test hang (original) (raw)

Martin v. L�wis martin@v.loewis.de
22 Jul 2003 00:15:48 +0200

Barry Warsaw <barry@python.org> writes:

% strace -p 26615 futex(0x82fb8c0, FUTEXWAIT, 0, NULL

NPTL. 'Nuff said.

Regards, Martin

P.S. Perhaps not: NPTL is the New Posix Threads Library, and it is an attempt to make pthreads both standards-conforming and efficient on Linux, by providing more kernel support, and building the library on tof of this kernel support; the futex syscall is one of the extensions. The NGPTL version of pthreads is supposed to be binary-compatible with the old LinuxThreads library.

Unfortunately, there appears to be a number of inconsistencies, which might be bugs in the application, bugs in NPTL, or mere failure to provide binary compatibility.

For some reason, Redhat decided to include NPTL with Redhat 9, even though it hasn't been released yet.

Unless you want to determine the cause of this problem, I recommend to turn off NPTL. There is some magic environment variable that allows to do that (LD_ASSUME_KERNEL), see

http://www.redhat.com/docs/manuals/linux/RHL-9-Manual/release-notes/x86/