Further reduce the number of semaphores used under --disable-spinlocks.

Per discussion, there doesn't seem to be much value in having
NUM_SPINLOCK_SEMAPHORES set to 1024: under any scenario where you are
running more than a few backends concurrently, you really had better have a
real spinlock implementation if you want tolerable performance.  And 1024
semaphores is a sizable fraction of the system-wide SysV semaphore limit
on many platforms.  Therefore, reduce this setting's default value to 128
to make it less likely to cause out-of-semaphores problems.
This commit is contained in:
Tom Lane 2016-04-18 13:33:06 -04:00
parent 8ce8307bd4
commit 75c24d0f74

View File

@ -57,7 +57,7 @@
* may improve performance, but supplying a real spinlock implementation is
* probably far better.
*/
#define NUM_SPINLOCK_SEMAPHORES 1024
#define NUM_SPINLOCK_SEMAPHORES 128
/*
* When we have neither spinlocks nor atomic operations support we're