Tarantool sphia make slow selects?

Question

Use tarantool version: Tarantool 1.6.8-586-g504e151 It installed from epel. I use tarantool on sphia mode:

log_space = box.schema.space.create('logs',
    {
        engine = 'sophia',
        if_not_exists = true
    }
)

log_space:create_index('primary', {
        parts = {1, 'STR'}
    }
)

I have 500.000 records and make select request:

box.space.logs:select({'log_data'})

it takes aboute 1min. Why so slow ?

unix/:/var/run/tarantool/g_sofia.control> box.stat()
—-
- DELETE:
    total: 0
    rps: 0
  SELECT:
    total: 587575
    rps: 25
  INSERT:
    total: 815315
    rps: 34
  EVAL:
    total: 0
    rps: 0
  CALL:
    total: 0
    rps: 0
  REPLACE:
    total: 1
    rps: 0
  UPSERT:
    total: 0
    rps: 0
  AUTH:
    total: 0
    rps: 0
  ERROR:
    total: 23
    rps: 0
  UPDATE:
    total: 359279
    rps: 17

Answer 1

After direct on-site help and debugging with agent-0007, we have found several issues.

Most of them been related to slow virtual environment (openvz been used), which shows inadequate pread() stalls and io timings.

Additionally we have found two integration issues:

https://github.com/tarantool/tarantool/issues/1411 (SIGSEGV in eio_finish) https://github.com/tarantool/tarantool/issues/1401 (Bug in upsert applier callback function using sophia)

Thanks.

Answer 2

Sophia engine is deprecated since 1.7.x . Please use vinyl engine instead of it.

Please take a look for more details: https://www.tarantool.io/en/doc/1.10/book/box/engines/vinyl/