weird memory consumption vs machine spec
Bizarre scenario, but we had an issue where the apps I run (40 sites running the same code) - were hitting out of memory exceptions since moving to a new bigger server (46 cores, 128GB ram) and the apps were consuming much more memory than they did on our old 24 core server with less ram.
To resolve temporarily I put them on a 32 core, 256GB ram server. (CPU count only changed because its what AWS offered) and the memory usage of each app has dropped back to how they used to behave.
We are currently using about 98GB (same as before we moved to the new 46 core server), so it's as if it needed the ram when only 128GB was available, we upgraded, now it doesnt need it anymore. The app usage appears to be consistent throughout.
Any ideas why this would happen?
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Unknown User•3w ago
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i do have a full memory dump of the "inflated" state, + DotMemory - I will grab one of the new slimmmer state and compare
Unknown User•3w ago
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I read that there is a per-core overhead for server GC but no idea if that is relevant
Unknown User•3w ago
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oh yeah ive been gathering the dumps out of hours
Unknown User•3w ago
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yeah, understood. I grabbed one right before machine went down for windows updates anyway
Unknown User•3w ago
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yeah its difficult to even see whats going on even with an app ive worked on a lot
Hi,
Dunno if it helps, but maybe a look at what kind of differences there are in the environment. Like OS, hypervisor, memory optimezed.
AWS seems to have different instances: https://aws.amazon.com/ec2/instance-types/
Amazon Web Services, Inc.
Cloud Compute Instances – Amazon EC2 Instance Types – AWS
Amazon EC2 instance types comprise varying combinations of CPU, memory, storage, and networking capacity. This gives you the flexibility to choose an instance that best meets your needs.
It's definitely got differnet spec CPU etc etc, but it shouldnt affect the memory usage of the app