parallel query not working

[George Merticariu]

if two retrieval (select) queries are executed, then the second one is waiting for the first one to finish.

e.g.

console 1: ./rasql -q 'select avg_cells(test - test/2 -test/3) from test' —out string

console 2: ./rasql -q 'select avg_cells(test - test/2 -test/3) from test' —out string

Result: Console 1 is executing, Console 2 is waiting → Console 1 finishes, Console 2 is executing → Console 2 finishes

[Dimitar Misev]

Hmm this shouldn't happen with select queries..

[Dimitar Misev]

We have a bit of a problem with SQLite that is just becoming apparent — SQLite is great for a multithreaded application, but not very optimal for our multiprocess environment.

I tend to think more and more that traditional PostgreSQL + filesystem for the tiles is the optimal backend for rasdaman.

[Peter Baumann]

maybe related to the recent SQLite wait patch?

[Peter Baumann]

maybe related to the recent SQLite patch?

[Dimitar Misev]

Yes most likely, but I didn't expect it to affect purely select queries. It needs to be revised.

[Dimitar Misev]

I submitted a patch, the issue was in starting IMMEDIATE transaction rather than regular one, which prevents other IMMEDIATE transactions to be started until it finishes.