Item5776: MailerContrib cannot run multiple instances at the same time (document this fact)

the support TWiki for MailerContrib

Turned out that the news and web notifies were running in parallel & interfering with each-other.

• This indicates missing synchronization (semaphore/lock) in the code; it should not be the user's responsibility to manage synchronization.
• Even if this is not fixed (and it should be), the restriction should be documented in the installation instructions.
• I provided a work-around script that consolidates all twiki maintenance (news/web notify, statistics, ticktwiki) into a single script/crontab entry. You might want to include it as an example in the documentation; it would avoid having others run into this trap. And it is somewhat more efficient than having several cron jobs.

This was quite painful to live with -- I'm marking it normal rather than urgent because there is now a work-around.

-- TWiki:Main/TimotheLitt - 14 Jul 2008

Note script is in TWiki:Support/DuplicateNotificationsFromMailerCon

-- TWiki:Main.KennethLavrsen - 14 Jul 2008

A docu update should be sufficient to close this one.

A lock mechanism is a bit of an overkill and risky in case a lock file is left behind after a crash.

The docu I added to the MailerContrib.txt file points to the support topic so people can take advantage of the suggested script should they desire.

-- TWiki:Main.KennethLavrsen - 27 Jul 2008