I tried to update a existing template (linked to ~ 200host) and it fails.

The apache2 says:

[Thu Aug 02 10:59:23 2012] [error] [client 172.24.52.182] PHP Fatal error: Allowed memory size of 1073741824 bytes exhausted (tried to allocate 71 bytes) in /data/zabbix/html/include/classes/debug/CProfiler.php on line 232, referer: http://zabbix-br.isc.ejpd.admin.ch/conf.import.php?rules_preset=template&sid=91ba1cbcbdae0be1

I've change in steps from the initial 12 to 256, 512,1024 and finally 2048 and there it worked.

Seems a lot of memory for me for this task...

Attached you'll find my little template