I have an overnight batch run which is transactional...picking up data doing some small calculations and putting it somewhere else and it was finishing around 3am every day for the last 2 months. Now it's spiked and finishes at just after 4.15am every day and I can't figure out why.
By calculations I mean simply data aggregation. Now I do know that there are some poorly written queries in it but I don't think they explain this hike.
- Data volumes have not changed significantly (given that it is transactional, it is always increasing by a fixed amount).
- There have been no hardware or software changes to server
- There have been no changes to the batch or the calculations it is doing.
- All parts of the batch seem to have increased by mostly the same percentage of time.
Part of me things this must be a hardware issue but I have no previous stats to compare against if I do benchmarks.
Could I have passed some sort of limit somewhere that I could not be aware of? Any ideas what these could be? Assume I have no experience as I don't want to discount anything...
I know its a long shot but has anyone got any ideas, based on experience, as to what might have caused this?
