Sudden slowdown

[GeoffM]

MantisBT Version 1.3.2
Schema Version 209
Windows IIS 8.5.9600.16384
Windows Server 6.2

MantisBT has been running great for years. Migrated to IIS a couple of years ago - again, no issues. In the last month however, any updates/inserts have become really slow, something like 30s each. SELECTs are fast, unless it's in the middle of an update/insert when it seems to wait for that to complete first. The email table is empty. There are no errors in the logfile, just a couple of warnings that don't appear relevant, and a bunch of notes. There are around 21500 tickets, certainly some files attached but not huge or too many, about 30 users, and no customisations. MySQL tools to check the tables and optimise them all returned OK very quickly. The same email server (hMailServer) is fine for the .NET part of the website (separate application pool, subdomain etc). I can't find any other useful ideas on this forum or elsewhere. Have I missed something?

Thanks.

[atrol]

Check if there are entries in mantis_email_table.
If so, there is a problem sending emails which might be the reason for your performance problem.

[GeoffM]

The email table is empty.

Check if there are entries in mantis_email_table.
If so, there is a problem sending emails which might be the reason for your performance problem.

[bodtx]

Check if there are entries in mantis_email_table.
If so, there is a problem sending emails which might be the reason for your performance problem.

Yes! this works for me in 2.26.0.
Mantis seems to try sending mail in this table each time a new mail is generated (ex: new issue assignment)

once the correct smtp host was configured (we've moved our smtp that's why mantis was broken), all emails in this table have been sent