On Tue, Dec 1, 2009 at 10:32 AM, Jeremy Adams <[email protected]> wrote:
> It depends. If the changeset is uploaded in small chunks to the API, each >> is written as a separate database transaction and the data will be spread >> across multiple minute diffs. If the data is uploaded in a single chunk it >> is written within a single database transaction and can possibly take longer >> than 30 minutes to process. The data only becomes visible to Osmosis after >> the transaction is committed by which time Osmosis has moved past that time >> interval and misses the data entirely. >> >> >>> >>> The fix seems to be using the new replication diffs, but TRAPI doesn't >>> support those yet. >>> >> >> Yes, they don't use timestamps at all so don't suffer from problems with >> long running transactions. If you see any missing data in those files, >> please let me know. >> >> > > Say I open a changeset and it takes an hour to upload. Is the data in the > changeset being written bit by bit as I'm uploading for that whole hour, or > is it stored until I'm done uploading and then written to the database as > one large transaction? If it's the latter, then I guess it doesn't matter > how long the changeset is open, only how long it takes the server to write > the changes to the database. > I assume you're referring to uploading an osc xml changeset to the API as opposed to opening a changeset explicitly and uploading each item individually. Honestly I have no idea how the API is implemented. I believe it makes changes bit by bit as it receives data but I don't know for sure. I just know that some database transactions remain open for longer than half an hour. > > Either way, the solution seems to be using the new replication diffs. I'm > no perl wizard, but I might try to muddle my way through and make some > changes. > The new files should be fairly similar to consume. The key difference is that each file may contain multiple changes for a single entity. In other words, you may receive a version 3 and 4 of an entity in a single diff file. Brett
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