PHP-5.3.5 + APC-3.1.7: apc.stat=0 has no effect ?

Hi! I'm trying to get rid of open/fstat syscalls by using apc.stat=0 but according to strace it has no effect... or maybe I'm doing something wrong. Here is my configuration: Linux Debian Squeeze, PHP-5.3.5 + APC-3.1.7 + php-fpm(all built from sources). APC settings: extension=apc.so apc.enabled=1 apc.shm_size=64M apc.ttl=7200 apc.user_ttl=7200 apc.slam_defense=0 apc.stat=0 PHP is not using safe_mode or open_basedir, realpath_cache_size = 512k, realpath_cache_ttl = 600 APC status page shows it's enabled. "strace"-ing a php-fpm process shows many entries in the following format: open("[path]/Foo.class.php", O_RDONLY) = 4 fstat(4, {st_mode=S_IFREG|0644, st_size=2579, ...}) = 0 fstat(4, {st_mode=S_IFREG|0644, st_size=2579, ...}) = 0 fstat(4, {st_mode=S_IFREG|0644, st_size=2579, ...}) = 0 mmap(NULL, 2579, PROT_READ, MAP_SHARED, 4, 0) = 0x7fae8d34a000 munmap(0x7fae8d34a000, 2579) = 0 close(4) Is it an expected behavior? -- Best regards, Pavel