Is there a any recommendation for tuning cache memory size?

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Hi,
We have a system that provides data entry on certain dates and times. You can think 2-3 days a week and at certain times of the day. Our data entries at these clocks are about 5 thousand series per second and we expect to increase. Our longest query interval is 12 hours. Our shard duration is 2 days and our retantion policy is 3 months.Our cache size configuration is cache-max-memory-size = 1073741824 and our snapshot configuration is cache-snapshot-memory-size = 26214400 and cache-snapshot-write-cold-duration = “10m0s”. Is our current configuration sufficient in such a system?

What size should I set to not get a “cache maximum memory size exceeded” error or where can I get a reference when I am configuring the cache size?
Also, do you have any suggestions for improving write and read performance?

Thank you for your advice.

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Hello @Ugur_Belge,
Welcome!
I wouldn’t change the defaults unless there is a specific tuning optimization that’s required.
That error means you aren’t able to write new data to disk fast enough to truncate the in-memory cache.
So you need to figure out why. It could be something physical - like the disk is too slow (or too busy); or it could be possibly improved by tuning. You can make the cache larger - and that sometimes helps - but really need to sort out why you can’t truncate the cache fast enough. If you have fast disks you are probably CPU bound and might benefit from increasing the limit. If they have slow disks then you’re going to struggle with their current write load.

Optimizing write performance:

Optimizing read performance: