Setting the Blob Cache
The blob cache is a disk cache of data in a remote object store.
Its size is controlled by the following engine variables:
maximum_which is set to a default value at startup based on the size of the disk that it is mounted on.
blob_ cache_ size_ mb
maximum_is zero by default and has no effect.
blob_ cache_ size_ percent
When the disk space on the disk it’s mounted on starts getting filled up and stored files/objects need more space, the blob cache starts shrinking itself.
maximum_ but then you can reset
maximum_ is the 'source of truth' and
maximum_ can be 'out of date' if you reset
maximum_ after setting
maximum_ will take priority and set
maximum_ to the corresponding value.
//Assume you are using a 1 TB disk andmaximum_blob_cache_size_mb = 800GB // for examplemaximum_blob_cache_size_percent = 0maximum blob cache size = 800GBSET maximum_blob_cache_size_percent = 0.50;//Nowmaximum_blob_cache_size_mb = 500GBmaximum_blob_cache_size_percent = 0.50maximum blob cache size = 500GBSET maximum_blob_cache_size_mb = 800GB;maximum_blob_cache_size_mb = 800GBmaximum_blob_cache_size_percent = 0.50maximum blob cache size = 800GB// On restarting the nodemaximum_blob_cache_size_mb = 500GBmaximum_blob_cache_size_percent = 0.50maximum blob cache size = 500GB
It is recommended not to use both variables at the same time, only one or the other.
Last modified: October 24, 2023