Improve locking behavior in indexes-only mode so we only need one
ACCESS EXCLUSIVE lock per table instead of one per index. Support
multiple --index options. Fix for schema-name parsing.
Patch from Beena Emerson.
Switch to using the two-input form of pg_advisory_lock(), so as
to avoid impacting other applications which might happen to lock
just the OID of the table. The REPACK_LOCK_PREFIX_STR is a decimal
version of the first three bytes of
echo -n "pg_repack" | sha1sum
Since we are not starting a new transaction in conn2 during the
swap step, we need to make sure that if our LOCK query is canceled
due to statement_timeout that conn2's transaction is not left in
a useless error state. Use SAVEPOINT and ROLLBACK TO SAVEPOINT to
avoid this problem.
--no-order now is almost useless, but list it next to --order-by.
--jobs only specifies how to do something, not what to do. On the
same basis probably --no-analyze should be pushed further up.
Note: if original namespace is "foo bar", repack_indexdef gives a bad
result. This is weird as apparently skip_ident can deal with spaces in
a quoted identifier. Committing as I'm going home, will deal with that
later.
Bumped version number to enforce extension re-creation as the SQL has
been modified.
Current limitations:
- Check for namespace existence: on error temp objects are left around
- What happens to the indexes?
- Tests needed.
- Should the default be the GUC default_tablespace instead of pg_default?
This is actually an original pg_repack shortcoming, not a regression.
This simplifies some of the error handling blocks, as now
we can unconditionally use this macro without worrying about multiple
PQclear() calls causing a double-free().
Per discussion with Daniele.
* Use poll() if it is available, or select() otherwise, to
efficiently wait on index builds in worker queries to finish.
* fix off-by-one error when initially assigning workers
* move PQsetnonblocking() calls to setup_workers()
Adds a new --jobs command-line argument to specify how many worker
connections you want. These worker connections should stick around
while processing table(s) in a single database. For each table,
parcel out the indexes to be built among these worker conns,
submitting each CREATE INDEX ... request using PQsendQuery() i.e.
in non-blocking fashion.
Most of this is still rather crude, in particular the
while (num_active_workers) ... loop in rebuild_indexes(), but
it seems to be working, so I'm committing here.
Code merged in, with a few more changes, from the multiple_tables branch.
The multiple --table support and SimpleStringList code is largely
borrowed from pg_dump. (pg_reorg Issue #18).
The concurrent DDL guard is implemented using an auxiliary
database connection (pg_reorg Issue #8) which holds an ACCESS SHARE
lock on the target table while pg_repack conducts the rest of its work.
