Tarantool sphia make slow selects? - tarantool

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

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/

Answer 2

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.