Re: [pysqlite] Erratic behavior under high loads, with APSW code sample

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For the record, APSW does not change SQLite's transaction behaviour in
any way.  It also does not attempt to parse and guess what your code is
doing.  This behaviour is not DBAPI compliant which is why pysqlite has
to do all those things :-)

Frank McIngvale wrote:
> Hi, I'm having a strange problem with APSW & pysqlite that shows up
> under higher loads.

Your problem is strange because you made the mistake of silently
ignoring all exceptions :-)

>  try:
> 	cur = conn.cursor()
> 		
> 	# record writer
> 	qs = 'insert into writers (pid,thread,nr) values (?,?,?)'
> 	cur.execute(qs, (os.getpid(), currentThread().getName(), nr))
> 		
> 	nr -= 1
> except:
> 	pass

If you remove the silent swallowing of all exceptions you'll find that
SQLite is returning busy errors.  If you add:

  conn.setbusytimeout(10000) # 10 seconds

Then you will find there are no exceptions and you get all 90 rows.  As
to why you see this on Linux, it is because of greater concurrency.

Roger
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