What:
Use the github.com/jackc/pgx postgresql driver in place of
github.com/lib/pq.
Why:
github.com/lib/pq has some problems with error handling and context
cancellations (i.e. it might even issue queries or DML statements more
than once! see https://github.com/lib/pq/issues/939). The
github.com/jackx/pgx library appears not to have these problems, and
also appears to be better engineered and implemented (in particular, it
doesn't use "exceptions by panic"). It should also give us some
performance improvements in some cases, and even more so if we can use
it directly instead of going through the database/sql layer.
Change-Id: Ia696d220f340a097dee9550a312d37de14ed2044
This attempts to add a README.md to help create consistent migrations
that maximize our test coverage and do not include unnecessary
statements.
It also adds a feature to have an `-- OLD DATA --` section as well
as a `-- NEW DATA --` section so that we can fix mistakes made in
previous snapshots (like a row that was forgotten to be added when a
table was created) without editing them going forward.
Change-Id: I28a786f8ef163cae1de1bb08f61af1e1104b0a88
it was noticed that if you had a long lived transaction A that
was blocking some other transaction B and A was being aborted
due to retriable errors, then transaction B was never given
priority. this was due to using savepoints to do lightweight
retries.
this behavior was problematic becaue we had some queries blocked
for over 16 hours, so this commit addresses the issue with two
prongs:
1. bound the amount of time we will retry a transaction
2. create new transactions when a retry is needed
the first ensures that we never wait for 16 hours, and the value
chosen is 10 minutes. that should be long enough for an ample
amount of retries for small queries, and huge queries probably
shouldn't be retried, even if possible: it's more preferrable to
find a way to make them smaller.
the second ensures that even in the case of retries, queries that
are blocked on the aborted transaction gain priority to run.
between those two changes, the maximum stall time due to retries
should be bounded to around 10 minutes.
Change-Id: Icf898501ef505a89738820a3fae2580988f9f5f4
Replace all the remaining uses of sql.DB with tagsql.DB to
fix issues with context cancellation.
Introduce tagsql.Open which helps to get rid of all tagsql.Wrap-s.
Use tagsql in cockroachkv and postgreskv.
Change-Id: I8946d203341cb85a25976896fc7881e1f704e779
Also added temporary types withRebind and withTagTx,
which will be later removed. Currently they help to avoid
changing the whole codebase at the same time.
Change-Id: I7f07ba8f4709a23a463bfa67464628665a05808f
dbschema.Query is used only for testing and sqlite,
so this won't cause us problems in production.
Change-Id: Ib296a7daf161a9d3de23a7dfdc4f505d47ac4a37
This reverts commit 8e242cd012.
Revert because lib/pq has known issues with context cancellation.
These issues need to be resolved before these changes can be merged.
Change-Id: I160af51dbc2d67c5449aafa406a403e5367bb555
this will allow for some nice runtime analysis down the road.
also, this allows for wrapping database handles in a way that
can interact with these contexts
requires https://review.dev.storj.io/c/storj/dbx/+/514
Change-Id: Ib087b7cd73296dd2c1e0331314da34d861f61d2b
This code needs to work against cockroachDB, so transactions must be retried
when a retryable error is returned. This change puts migrate
transactions into the dbutil.WithTx transactional helpers to achieve
this in the easiest way.
Change-Id: Ib930e82d55cb0257357a222ce9131e6e53372c03
