[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Keith Medcalf
On Monday, 18 April, 2016 08:47 Olivier Mascia wrote: > Just to clarify: you mean compiled using SQLITE_CONFIG_MULTITHREAD (and > not SQLITE_CONFIG_SERIALIZED), is that it? > Then, if using threads in the application, each thread has its own > connection (or multiple connections) but no thread

[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Olivier Mascia
> Le 18 avr. 2016 ? 15:10, Detlef Golze a ?crit : > > thank you for the hints. I think I do it correctly, I compiled with > SQLITE_CONFIG_MULTITHREAD and attach the database with the URI option > cache=shared. Do you really *need* to use shared cache in favor of private cache? There are more

[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Clemens Ladisch
Detlef Golze wrote: > I attach the database with the URI option cache=shared. This makes all threads share a single connection. Don't do it. Regards, Clemens

[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Simon Slavin
On 18 Apr 2016, at 2:10pm, Detlef Golze wrote: > I compiled with SQLITE_CONFIG_MULTITHREAD That bit's okay. > and attach the database with the URI option cache=shared Try turning that bit off and see if it results in an overall speed-up. Simon.

[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Olivier Mascia
> Le 18 avr. 2016 ? 14:17, Detlef Golze a ?crit : > > Hi, > > I am using SQLite C amalgamation version 3.08.11.01 compiled for Multi > Threading Mode and using WAL Journal Mode. > > Sometimes I need to execute a SELECT statement which takes a very long time > to complete. I realized that dur

[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Detlef Golze
> Detlef Golze wrote: > > I attach the database with the URI option cache=shared. > > This makes all threads share a single connection. Don't do it. > > > Regards, > Clemens That was indeed the problem. During my initial tests this option provided the best performance. I probably need to re-t

[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Detlef Golze
, April 18, 2016 2:47 PM To: SQLite mailing list Subject: Re: [sqlite] UPDATE/open/close blocked while executing SELECT > Le 18 avr. 2016 ? 14:17, Detlef Golze a ?crit : > > Hi, > > I am using SQLite C amalgamation version 3.08.11.01 compiled for Multi > Threading Mode and

[sqlite] UPDATE/open/close blocked while executing SELECT

2016-04-18 Thread Detlef Golze
Hi, I am using SQLite C amalgamation version 3.08.11.01 compiled for Multi Threading Mode and using WAL Journal Mode. Sometimes I need to execute a SELECT statement which takes a very long time to complete. I realized that during that time other functions are blocked for a significant amount o