[IGNITE-17406] SQL "select by key" performance 50-60 times slower than key-value get

• Type: Task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Labels: ignite-3 ignite3_performance
• Epic Link: AI3 Performance
• Assignee: Unassigned
• Reporter: Kirill Gusakov
• Created: 21/Jul/22 14:35
• Updated: 15/May/23 14:17

Description

During the https://issues.apache.org/jira/browse/IGNITE-17220 benchmarks runs we found out, that YCSB benchmarks show very slow performance.

1. After some investigations under https://issues.apache.org/jira/browse/IGNITE-17379 we found out, that SQL select by key performance significantly slower, than the same key-value get: 1-2ms vs 40-50ms.

Step to reproduce:

• clone branch https://github.com/gridgain/apache-ignite-3/tree/ignite-17379
• run test ItBenchmarkTest#testYCSBLikeKV

2. Also, at the same time it looks like performance degradation depends on the size of table data

Step to reproduce:

• run the test ItBenchmarkTest#testReadDegradationSqlApi

 

According to these points, it seems that the cause of these issues: "rocksdb full scan and post-filtering" pattern, which we are using in SQL API (fix me, if I'm wrong). You can check async-profile cpu flamegraph from the benchmarks run on my machine (RocksIterator#seek0 column, I guess)

 

Issue Links

• is duplicated by: IGNITE-17403 SQL "select by key" performance 50-60 times slower than key-value get
• is duplicated by: IGNITE-17404 SQL "select by key" performance 50-60 times slower than key-value get
• is duplicated by: IGNITE-17405 SQL "select by key" performance 50-60 times slower than key-value get
• is related to: IGNITE-17379 Investigate main bottlenecks in YCSB benchmark