Do you sometimes find anvil missing? I wonder if you can strace master and see what it is doing or waiting for...
This happened again this morning. I see the anvil process died -
22815 ? Z 0:13 [anvil] <defunct>
# strace -p 22799 Process 22799 attached - interrupt to quit futex(0xb7bc2bec, FUTEX_WAIT, 2, NULL <unfinished ...>
That's all there was from strace.
...maybe I better build a new postfix package and drop it on the centos list if there is not one there already.
I do not have any such issues with 2.3.5 but then I am using that on Centos 4.x