On 27/04/13 18:05, David Jordan wrote:
Thanks once again, Andy.
Perhaps the most relevant line from the transaction web page is the
following sentence: "A TDB-backed dataset can be used
non-transactionally but once used in a transaction, it should be used
transactionally after that."
I had been using it non-transactionally, which seemed to work fine.
But then I put in some use of TDB transactions for some updates, but
not for some updates are for any read accesses, and that is when the
problems started showing up. The docs read as if encasing read
operations in a read transaction are not going to impact performance,
so I will convert everything to be transaction based. It is
unfortunate that there does not seem to be a single, consistent API
for doing transactions that works for both TDB and SDB. But based on
the performance numbers we have been getting, I think we will stick
with TDB, SDB was just too slow.
Read transactions are cheap; they are very cheap when there isn't a
writer around at the point when it starts becaus ethen they are no more
than a read-only wrapper on the raw database.
Yes - it would be nice to have a consistent API. History mainly. They
could be brought back together if one or more people step in to
contribute to SDB.
Andy
