Forum Discussion
__lll_lock_wait allowing only one thread to work
I am calling the XPRESS optimizer from a multithreaded Pascal application and having performance issues with the solver. While the program is multithreaded, all but one of the threads are sleeping a...
I set the ulimit -n to 100K and now it doesn't appear to fail anymore.
The issue is now finding out why threads are waiting for a mutex on a function that one would expect to be able to run in parallel threads.
(gdb) info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fe7740 (LWP 2095381) "cmdopt_xprs" 0x00007ffff7bbe3fc in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
2 Thread 0x7ffff0678700 (LWP 2096062) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
3 Thread 0x7ffff0277700 (LWP 2096063) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
4 Thread 0x7fffefe76700 (LWP 2096064) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
5 Thread 0x7fffefa75700 (LWP 2096065) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
6 Thread 0x7fffef674700 (LWP 2096066) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
7 Thread 0x7fffef273700 (LWP 2096067) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
8 Thread 0x7fffeee72700 (LWP 2096068) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
9 Thread 0x7fffeea71700 (LWP 2096069) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
10 Thread 0x7fffee670700 (LWP 2096070) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
11 Thread 0x7fffee26f700 (LWP 2096071) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
12 Thread 0x7fffede6e700 (LWP 2096072) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
13 Thread 0x7fffeda6d700 (LWP 2096073) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
14 Thread 0x7fffed66c700 (LWP 2096074) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
15 Thread 0x7fffed26b700 (LWP 2096075) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
16 Thread 0x7fffece6a700 (LWP 2096076) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
17 Thread 0x7fffeca69700 (LWP 2096077) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
18 Thread 0x7fffec668700 (LWP 2096078) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
19 Thread 0x7fffaffff700 (LWP 2096079) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
20 Thread 0x7fffafbfe700 (LWP 2096080) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
21 Thread 0x7fffaf7fd700 (LWP 2096081) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
22 Thread 0x7fffaf3fc700 (LWP 2096082) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
23 Thread 0x7fffaeffb700 (LWP 2096083) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
24 Thread 0x7fffaebfa700 (LWP 2096084) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
25 Thread 0x7fffae7f9700 (LWP 2096085) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
26 Thread 0x7fffae3f8700 (LWP 2096086) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
27 Thread 0x7fffadff7700 (LWP 2096087) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
28 Thread 0x7fffadbf6700 (LWP 2096088) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
29 Thread 0x7fffad7f5700 (LWP 2096089) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
30 Thread 0x7fffad3f4700 (LWP 2096090) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
31 Thread 0x7fffacff3700 (LWP 2096091) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
32 Thread 0x7fffacbf2700 (LWP 2096092) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
33 Thread 0x7fffac7f1700 (LWP 2096093) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
34 Thread 0x7fff6bfff700 (LWP 2096094) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
35 Thread 0x7fff6bbfe700 (LWP 2096095) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
36 Thread 0x7fff6b7fd700 (LWP 2096096) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
37 Thread 0x7fff6b3fc700 (LWP 2096097) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
38 Thread 0x7fff6affb700 (LWP 2096098) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
39 Thread 0x7fff6abfa700 (LWP 2096099) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
40 Thread 0x7fff6a7f9700 (LWP 2096100) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
41 Thread 0x7fff6a3f8700 (LWP 2096101) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
42 Thread 0x7fff69ff7700 (LWP 2096102) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
43 Thread 0x7fff69bf6700 (LWP 2096103) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
44 Thread 0x7fff697f5700 (LWP 2096104) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
45 Thread 0x7fff693f4700 (LWP 2096105) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
46 Thread 0x7fff68ff3700 (LWP 2096106) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
47 Thread 0x7fff68bf2700 (LWP 2096107) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
48 Thread 0x7fff687f1700 (LWP 2096108) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
49 Thread 0x7fff2bfff700 (LWP 2096109) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
50 Thread 0x7fff2bbfe700 (LWP 2096110) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
51 Thread 0x7fff2b7fd700 (LWP 2096111) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
52 Thread 0x7fff2b3fc700 (LWP 2096112) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
53 Thread 0x7fff2affb700 (LWP 2096113) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
54 Thread 0x7fff2abfa700 (LWP 2096114) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0
55 Thread 0x7fff2a7f9700 (LWP 2096115) "cmdopt_xprs" 0x00007ffff7bc175d in __lll_lock_wait () from /lib64/libpthread.so.0They are all waiting after the call to XPRSmipoptimize.
Thank you very much, Daniel. You've been very helpful every time I asked for help on this forum.