On Wed, March 14, 2007 14:08, Will McDonald wrote (trimmed): > On 14/03/07, Ryan Simpkins <centos at ryansimpkins.com> wrote: >> Try doing a simple 'cat /var/log/maillog | grep -c check_relay' > > You can avoid the unnecessary 'cat' by just passing the filename to grep directly: > > # grep -c 'checK_relay.*spamhaus' /var/log/maillog > # grep -c 'checK_relay.*spamcop' /var/log/maillog > # grep -c 'checK_relay.*njabl' /var/log/maillog > > Would probably be more efficient and faster, you can test with 'time' to verify this. You're spawning one process 'grep', instead of three seperate processes, 'cat, 'grep' and 'grep' again. Am I using time right to measure it? # time cat /var/log/maillog | grep check_relay | grep -c njabl 8 real 0m0.299s user 0m0.289s sys 0m0.009s # time grep -c 'check_relay.*njabl' /var/log/maillog 8 real 0m0.404s user 0m0.402s sys 0m0.000s Is the first 'time' measuring the whole one-liner, or just the time it takes to 'cat'? I also tried this: time echo `cat /var/log/maillog | grep check_relay | grep -c njabl` 8 real 0m0.325s user 0m0.312s sys 0m0.012s time echo `grep -c 'check_relay.*njabl' /var/log/maillog` 8 real 0m0.411s user 0m0.408s sys 0m0.002s I ran these several times mixed back and forth to try and see if they were flukes, these numbers appear to be representitive of the average. What do you get on your system? Maybe passing the file name to grep gets faster as the file size increases? wc /var/log/maillog 12323 142894 1588860 /var/log/maillog I wonder if the issue here is actually the 'stuff*morestuff' as that might be a more expensive match: time echo `grep -c 'check_relay' /var/log/maillog | grep njabl` real 0m0.269s user 0m0.263s sys 0m0.006s -Ryan