Hello Sumit,
By default, ASE uses a method to increase the number of pages acquired from the procedure cache pool if they are repeatedly requested by the same spid. The idea is to reduce the number of times that the spid needs to ask for memory under spinlock by giving "repeat customers" more than they asked for.
When you use traceflag 753, it disables this processing and only supplies the requested memory.
Some key points:
- memory is allocated in 2K pages
- each engine has a cache of memory that can be used for single-page requests
- memory supplied from the engine cache does not require the spinlock
- multiple page requests (such as the optimization described above) must be supplied from the global pool and requires spinlock protection
We have seen that some customers benefit from traceflag 753 because the single-page requests are satisfied from the engine cache and thus avoid the spinlock. This benefit outweighs the default processing for these customers. Traceflag 753 is not for everyone, but if you are seeing high CPU utilization related to the procedure cache spinlock contention, then it is worth trying.
Regards,
Mark Kusma