In cassandra maximum memory usage (536870912 bytes), cannot allocate a piece of 1048576 bytes

Question

I am using apache cassandra-3.0.6, 4 node cluster, RF = 3, CONSISTENCY - '1', Heap 16GB.

Im getting an informational message in system.log as " INFO [SharedPool-Worker-1] 2017-03-14 20: 47: 14,929 NoSpamLogger.java:91 - The maximum memory usage has been reached (536870912 bytes), it is impossible to allocate a piece of 1048576 bytes "

I don’t know exactly what memory he means, and I tried by increasing the file_cache_size_in_mb file to 1024 out of 512 in the Cassandra.yaml file. But again, he instantly filled the remaining 512 MB and stopped recording the application, showing the same informational message as " INFO [SharedPool-Worker-5] 2017-03-16 06: 01: 27,034 NoSpamLogger.java:91 - Maximum memory usage reached (1073741824 bytes), cannot allocate a piece of 1048576 bytes "

suggest someone run into the same problem ... Thanks!

Bhargav

Answer 1

As far as I can tell from Cassandra 3.11, no matter how big you set file_cache_size_in_mb , you will still get this message. The cache fills up and writes this useless message. In my case, this happens regardless of whether I installed 2 GB or 20 GB. This may be a mistake in the cache removal strategy, but I cannot say.