Hi, Tom Hughes wrote: >> Could Postgres be persuaded to abort any transaction that runs longer >> than "n" minutes (e.g. 30), and the we run the hourlies at hh:31 or so? >> That would probably be a slight inconvenience to those who happen to >> start 35-minute transactions but they should just learn to do their bulk >> imports properly ;-) > > Um... Are you being serious?
Yes. In most cases, whatever HTTP client they were using to upload will already have terminated the TCP connection and complained about a timeout anyway, leading them to upload the same thing again... > You want us to arbitrarily abort otherwise > valid changeset uploads? For the sake of the greater good of course ;-) > Why? We've already solved the problem with the transactional diffs... For many uses, I view the hourly diffs as superior as they will contain less "noise" (edits that cancel each other out will not be present in the hourlies). So I would really like to have reliable hourly diffs - even if they come with a considerable delay. My reasoning is that I feel uneasy when these transactions are completely unlimited. For all I know, there might be a freak case where a transaction runs for 8 days and I suddenly have an object in this week's planet which is 8 days old but wasn't in last week's planet (etc.). (Incidentally, what happens to a changeset in these cases? Normally a changeset would self-close after 1hr idle time. Suppose someone starts a transaction on a changeset that lasts 90 minutes. If I retrieve the changeset after 61 minutes, will the API tell me that the changeset is still open but has had no edits in the last 61 minutes - or will the API tell me that the changeset is closed and contains no edits, and when I re-check an hour later, the changeset suddenly has 5000 edits?) So I would like to have *some* certainty about the run time of transactions. Even if it is 24 hours or so - just some value where I know that no transaction can possibly exceed this duration. And if we should find that only one promille of all transactions takes longer than thrity minutes then I'd be prepared to sacrifice that one transaction if that buys me accurate hourly diffs at 31 minutes past the hour. Bye Frederik _______________________________________________ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev
