[sde]

this is an ajax front end to system information. updating the UI through ajax is expensive, so i only want to do it when something has changed in a log file.

the system will not be able to notify the web client directly, so i will need js->php to get server-side info.

if i had a listener app writing to mysql, then php polling for changes, it would be more expensive than php just looking directly at the file.

so i guess the question was more like this: within PHP, what uses less resources, checking the file size, change time, or something else that would allow me to detect a change.