Sergey Lapukhov created CASSANDRA-14069: -------------------------------------------
Summary: Node stopped serving write requests when a table has a lot of sstables Key: CASSANDRA-14069 URL: https://issues.apache.org/jira/browse/CASSANDRA-14069 Project: Cassandra Issue Type: Bug Components: Core Reporter: Sergey Lapukhov Attachments: create.cql, stack.txt Cluster was flooded with SSTables. A table had ~20000 sstables. Write requests started failing. Steps to reproduce: * Create cluster with 3 nodes * Specify {{memtable_heap_space_in_mb: 10}} in cassandra.yaml * Create table standard1 in keyspace1 (for the cassandra-stress tool) with the script [^create.cql]. Please note {{ compaction = {'class': 'SizeTieredCompactionStrategy', 'enabled': 'false'} }} - i.e. node will not perform compaction. * Populate node with data: {{cassandra-stress write n=1000000000 -node 127.0.0.1}} * After node was populated, put both read and write pressure on it: {{cassandra-stress read n=1000000000 -node 127.0.0.1 cassandra-stress write n=1000000000 -node 127.0.0.1}} * While still under pressure, enable LeveledCompactionStrategy {{echo "ALTER TABLE keyspace1.standard1 WITH compaction = { 'class' : 'LeveledCompactionStrategy', 'sstable_size_in_mb' : 1 }; DESC keyspace1.standard1; exit" | bin/cqlsh;}} *Results:* Write requests failing, read requests still processed. 'bin/nodetool cfstats' and 'bin/nodetool compactionstats' commands hanging, if issued from the node running cassandra-stress tool. If issued from another node: {{$ bin/nodetool cfstats ... Table: standard1 SSTable count: 22637 SSTables in each level: [22651/4, 0, 0, 0, 0, 0, 0, 0, 0] ...}} {{$ bin/nodetool compactionstats pending tasks: 12656 id compaction type keyspace table completed total unit progress 935bbc00-d03b-11e7-a47d-2b44293495b8 Compaction keyspace1 standard1 59556014 59557860 bytes 100.00% a29ee660-d03b-11e7-a47d-2b44293495b8 Compaction keyspace1 standard1 80432114 742151655 bytes 10.84% 9766e400-d03b-11e7-a47d-2b44293495b8 Compaction keyspace1 standard1 58891604 58893215 bytes 100.00% 9cdc9880-d03b-11e7-a47d-2b44293495b8 Compaction keyspace1 standard1 20289449 20290800 bytes 99.99% 90f98910-d03b-11e7-a47d-2b44293495b8 Compaction keyspace1 standard1 59689824 59695545 bytes 99.99% 986ede20-d03b-11e7-a47d-2b44293495b8 Compaction keyspace1 standard1 40598594 40598820 bytes 100.00% 9cd322a0-d03b-11e7-a47d-2b44293495b8 Compaction keyspace1 standard1 60756739 60766660 bytes 99.98% }} Special note about 'bin/nodetool compactionstats' - picture above is quite typical for this issue. I.e. compaction tasks manage to make it through, but hinder near the full completion (around 99.9 %). -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org