I have last mod_qos 8.13 enabled.
If i add this line in all virtual hosts:
QS_LocRequestLimit / 10
then apache not run. In error log i have this lines repeated with every start attempt
[Sat Aug 08 22:36:32 2009] [emerg] mod_qos(007): could not determine MaxClients
[Sat Aug 08 22:36:32 2009] [emerg] mod_qos(004): could not create a-mutex: No space left on device
Disk space is not a problem.
I think.. problem can be in too many virtualhosts? Number is 634. If I add line in just one, then all is ok.
Maybe too many semaphores? I don't know.