HELIOS Tech Info #158

HELIOS server products on OS X

HELIOS server processes use file caches for better performance. These caches are now extended in the UB64 release and the open file count per process has been increased.

This leads to an OS X issue because a Mac can only manage 12288 open files at all. To verify, become 'root' on a shell and enter the command
sysctl -a

It shows among others
kern.maxfiles = 12288

Therefore it is not possible to use that many open files for caching as on other platforms, and so it is not possible to use the OS X platform as a server for many connected users.

Due to this limitation we did not increase the open files count on OS X as on other platforms.
On OS X, PCShare UB2 and UB64 use a default of 2048 open files per user maximum. Other platforms are increased to 8192 in UB64.

Note: This limitation is caused by a limit of OS X and OS X Server. Therefore only a small user count can be used or the number of open files must be further decreased. To adjust the file count the following commands can be used:
prefvalue -k Programs/pcshare/files -t int 512
prefvalue -k Programs/afpsrv/files -t int 512

The file count above allows, for example, a user count of 20 users.