properly.
Remove SGML docs about openjade performance patch, and instead add
comment in style sheet where indenting code is commented out.
Backpatch to 8.2.X.
>
> * Embedded server (not wanted)
>
> While PostgreSQL clients runs fine limited-resource environments, the
> server requires multiple processes and a stable pool of resources to
> run reliabily and efficiently. Stripping down the PostgreSQL server
> to run in the same process address space as the client application
> would add too much complexity and failure cases.
< * Have EXPLAIN ANALYZE highlight poor optimizer estimates
> * Have EXPLAIN ANALYZE issue NOTICE messages when the estimated and
> actual row counts differ by a specified percentage
in normal operation, and we can avoid rewriting pg_control at every log
segment switch if we don't insist that these values be valid. Reducing
the number of pg_control updates is a good idea for both performance and
reliability. It does make pg_resetxlog's life a bit harder, but that seems
a good tradeoff; and anyway the change to pg_resetxlog amounts to automating
something people formerly needed to do by hand, namely look at the existing
pg_xlog files to make sure the new WAL start point was past them.
In passing, change the wording of xlog.c's "database system was interrupted"
messages: describe the pg_control timestamp as "last known up at" rather than
implying it is the exact time of service interruption. With this change the
timestamp will generally be the time of the last checkpoint, which could be
many minutes before the failure; and we've already seen indications that
people tend to misinterpret the old wording.
initdb forced due to change in pg_control layout. Simon Riggs and Tom Lane
identify long-running transactions. Since we already need to record
the transaction-start time (e.g. for now()), we don't need any
additional system calls to report this information.
Catversion bumped, initdb required.
locks that logically should not be released, because when a subtransaction
overwrites XMAX all knowledge of the previous lock state is lost. It seems
unlikely that we will be able to fix this before 8.3...
subtransaction are released if the subtransaction aborts --- in user-level
terminology, this means either rolling back to a savepoint or escaping from
a plpgsql exception block. Per recent suggestion from Simon.
