- Previously, on timequantum schemas, we would
create and open a view for the cartesian
product of every possible view and shard.
- This caused us to be very slow on re-open,
and to use lots of memory for views that
held nothing.
- This change makes startup faster, memory
use much lower, and should speed migration.
- default Tx is once again RBF, changed from bolt.
- document the RBF code review comments that were not addressed
before #1052 was merged, so they don't get lost.
- they should be easily addressed by replaying the entire WAL file
rather than from the DB meta page 0 notion of the last WalID
- cleanup rbf/cfg/cfg.go stale comments, ensure default0 respected.
1 msec checkpoint time, 1MB wal segment defaults.
- return a specific error, ErrNoMetaFound, from findNextWALMetaPage()
rather than io.EOF, since there actually wasn't any file IO involved.
- add http handlers for /cpu-profile/start and /cpu-profile/stop
in http/handler.go enable CPU profiling at specific time points
during an ingest or other operation.
- to indicate that the query context is already
done.
- handles the case where the import worker is
interrupted early by a ctx cancellation,
thus avoiding a panic.
Our nightly CI has been failing for a week due to WAL issues and it's
making it difficult for Kuba and Antonio to do things on the
integration repo. Hoping bolt backend will solve that in the short
term. I think the issue is Pilosa #1046 (that's from memory though)
Per slack discussion with Seebs and Nia,
we'll try not automatically resetting the Qcx.
The worry was that our goroutine shutdown
management is so poor that we are asking for
GetTx on a goroutine that still has a Qcx
from a query that was cancelled.
If this is the case, we will now panic instead of
issuing a new Tx. Then we can fix the poor
goroutine management.
- also require Qcx.Finish or Abort before Reset
- only allocate the rowcache if it is in use (avoid allocation per fragment)
- when the rowcache is use, fragment.go intRowIterator must write lock the
fragment because the f.rowCache will be updated.
- eliminate unused bitmapCache interface to keep the linter happy.
- fixes#1035
- view.openFragmentInTx was forcing a directory scan
for shards on every open fragment during Holder.Open().
Seen by pprof profile having excessive allocations
from dbshard.go listDirUnderDir().
- fix a CI/Makefile issue that was hiding red tests in CI.
- the testv and testv-race targets now require /bin/bash
- In executor.go, the top-level query context Qcx now
has a write flag. It will upgrade read-Tx to write-Tx
when Store() wraps some inner local-read operations,
to avoid deadlocking against its own query. This deadlock
happens in TestExecutor_Execute_SetRow/Set_NewRow
under rbf_lmdb blue-green testing without the upgrade.
- correct string constants for txtype so that
blue-green cleanup correctly detects when
2nd transaction in a pair has Committed and
thus the blue-green RWMutex can be relased
- test that txtype.String() is consistent with
the corresponding string constants.
- document in bluegreentx.go the current limitations
of blue-green testing: only one github archive import
(a single writing client) is supported by blue-green
testing. Multiple importers will deadlock eventually
on the DBShard.mut RWMutex. We could fix this by
ordering the write locks and obtaining them in
strictly increasing order (by shard number), but
that would require alot of change to the executor
and that would introduce more risk for a test-only
pathway.
- allows blue-green testing with concurrent readers/writers.
- otherwise we don't start/end the blue and green Tx
together, and they get split by a read/write concurrently.
