Re: [sqlite] very slow fdsync() calls

2014-03-20 Thread Kees Nuyt
On Thu, 20 Mar 2014 18:05:48 +1300, Jono Poff wrote: > and I can't easily > change the page size of the db either. You may have other reasons why you can't do it easily, but PRAGMA page_size=newpagesize; VACUUM; will convert to newpagesize. -- Groet,

Re: [sqlite] very slow fdsync() calls

2014-03-19 Thread Jono Poff
On 20/03/2014 5:14 p.m., Nico Williams wrote: On Wed, Mar 19, 2014 at 8:03 PM, Jono Poff wrote: On 12/03/2014 12:01 p.m., Nico Williams wrote: ZFS recordsize Hi Nico, I have one (or two) last question(s)... All I need to do is prevent a single process ('process

Re: [sqlite] very slow fdsync() calls

2014-03-19 Thread Nico Williams
On Wed, Mar 19, 2014 at 8:03 PM, Jono Poff wrote: > On 12/03/2014 12:01 p.m., Nico Williams wrote: >> >> ZFS recordsize > > Hi Nico, > > I have one (or two) last question(s)... > > All I need to do is prevent a single process ('process A') from being time > bound by

Re: [sqlite] very slow fdsync() calls

2014-03-19 Thread Jono Poff
On 12/03/2014 12:01 p.m., Nico Williams wrote: ZFS recordsize Hi Nico, I have one (or two) last question(s)... All I need to do is prevent a single process ('process A') from being time bound by making fsync() calls that clash with fsync() calls from other processes using other files in the

Re: [sqlite] very slow fdsync() calls

2014-03-12 Thread Jono Poff
Thankyou both for the suggestions. I set locking_mode=EXCLUSIVE and journal_mode=PERSIST but sqlite still fsyncs the directories. I'll try building with SQLITE_DISABLE_DIRSYNC, but hoping for a config only fix :) I'll post another question to the list when I've explored these options a bit

Re: [sqlite] very slow fdsync() calls

2014-03-11 Thread Nico Williams
On Mon, Mar 10, 2014 at 7:01 PM, Jono Poff wrote: > I'm using Solaris 10 with zfs and I may be able to disable write caching on > the entire disk, but would prefer not to! Any ideas appreciated. The way ZFS works, if you don't have a ZIL (ZFS Intent Log) device then

Re: [sqlite] very slow fdsync() calls

2014-03-11 Thread Simon Slavin
On 11 Mar 2014, at 12:20pm, Dan Kennedy wrote: > Or "PRAGMA locking_mode=EXCLUSIVE; PRAGMA journal_mode=PERSIST;", > if there will only ever be a single connection to the database. > > Or you could build with SQLITE_DISABLE_DIRSYNC, which omits all > syncs on

Re: [sqlite] very slow fdsync() calls

2014-03-11 Thread Dan Kennedy
On 03/11/2014 07:01 AM, Jono Poff wrote: Hi, I have an application that uses sqlite3. Investigating a problem with the app stalling occasionally I found that (every hour or two) an fdsync() system call from sqlite3_step() was taking over 3 seconds to return. On closer investigation, the

[sqlite] very slow fdsync() calls

2014-03-11 Thread Jono Poff
Hi, I have an application that uses sqlite3. Investigating a problem with the app stalling occasionally I found that (every hour or two) an fdsync() system call from sqlite3_step() was taking over 3 seconds to return. On closer investigation, the file descriptor in these calls point to the