When a meta query does not include a time component then it can be
answered exclusively by the index. This should result in a much faster
query execution that if the TSM engine was engaged.
This commit rewrites the following queries such that they make use
of the index where no time component is present:
- SHOW MEASUREMENTS
- SHOW SERIES
- SHOW TAG KEYS
- SHOW FIELD KEYS
Fixes#8819.
Previously, the process of dropping expired shards according to the
retention policy duration, was managed by two independent goroutines in
the retention policy service. This behaviour was introduced in #2776,
at a time when there were both data and meta nodes in the OSS codebase.
The idea was that only the leader meta node would run the meta data
deletions in the first goroutine, and all other nodes would run the
local deletions in the second goroutine.
InfluxDB no longer operates in that way and so we ended up with two
independent goroutines that were carrying out an action that was really
dependent on each other.
If the second goroutine runs before the first then it may not see the
meta data changes indicating shards should be deleted and it won't
delete any shards locally. Shortly after this the first goroutine will
run and remove the meta data for the shard groups.
This results in a situation where it looks like the shards have gone,
but in fact they remain on disk (and importantly, their series within
the index) until the next time the second goroutine runs. By default
that's 30 minutes.
In the case where the shards to be removed would have removed the last
occurences of some series, then it's possible that if the database was already at its
maximum series limit (or tag limit for that matter), no further new series
can be inserted.
* Fprint* functions
* No nakedness
* clarify panic messages
* spacing between case statements
* remove break in favor of return
* remove goto in favor of for { continue }
All of these services start up goroutines and then wait for the
goroutines to finish. Each of them has a `tsdb.PointBatcher` that may
return a point during the shutdown sequence. During the shutdown
sequence, a lock was held. This lock may get accessed when attempting to
write the point that came back from the `tsdb.PointBatcher`. This caused
the read lock attempt to wait forever for the write lock to be unlocked
during `Close()`.
This modifies these methods so that the write lock is released while
waiting for goroutines to finish in these three services.
Adds a new package prometheus for converting from remote reads and writes to Influx queries and points. Adds two new endpoints to the httpd handler to support prometheus remote read at /api/v1/prom/read and remote write at /api/v1/prom/write.
The only thing used from Prometheus is the storage/remote files that are generated from the remote.proto file. Copied that file into promtheus/remote package to avoid an extra dependency.
There are several places in the code where comma-ok map retrieval was
being used poorly. Some were benign, like checking existence before
issuing an unconditional delete with no cleanup. Others were potentially
far more serious: assuming that if 'ok' was true, then the resulting
pointer retrieved from the map would be non-nil. `nil` is a perfectly
valid value to store in a map of pointers, and the comma-ok syntax is
meant for when membership is distinct from having a non-zero value.
There was only one or two cases that I saw that being used correctly for
maps of pointers.
Other applications or services sometimes expose a header containing a
unique ID, which can then be included in logging or response information
to allow an operator to link inter-service requests. The most common
header name used by services in the wild appears to be `X-Request-ID`,
but `Request-Id` is also used.
This commit adds support for specifying either `X-Request-ID` or
`Request-Id` headers, which will then be used by InfluxDB when logging
request information, and also in the `X-Request-ID` and `Request-Id`
response headers.
We populate both `X-Request-ID` and `Request-Id` to maintain backwards
compatibility with previous version, and to support the more common
`X-Request-ID` header name.
If both `X-Request-ID` and `Request-Id` are specified, then
`X-Request-ID` is used.
If neither header is specified, then in line with previous behaviour, we
generate a v1 UUID.
The ConditionExpr function is more accurate because it parses the
condition and ensures that time conditions are actually used correctly.
That means that attempting to combine conditions with OR will not result
in the query silently pretending it's an AND and nested conditions work
correctly so there is only one way to read the query.
It also extracts the non-time conditions into a separate condition so we
can stop attempting to parse around the time conditions in lower layers
of the storage engine. This change does not remove those hacks, but a
following commit should be able to sanitize the condition and remove
them.
This commit provides more insight into server errors by both setting
the error on a response header, and, in the case of server errors (5xx),
logging those error messages to the HTTPD log, if [http] log_enabled =
true.
This change provides a clear separation between the query engine
mechanics and the query language so that the language can be parsed and
dealt with separate from the query engine itself.
This calculates the start and end time along with any time zones shifts
so that continuous queries are run at the correct time when a time zone
is included in the query.
Removing the forced `Connection: close` header from the `/query`
endpoint. This was originally added because of golang/go#13165, but it
seems like it's possible to use pipelining with go 1.8 and http 1.1,
just not recommended.
After some testing, it appears that the channel returned by
`ResponseWriter.CloseNotify()` will not send a value if the connection
was not interrupted. We already account for this in /query by exiting
from the goroutine if the request has finished by signaling another
channel.
Since the handler already accounts for the possibility that the channel
will not signal and since `CloseNotify()` doesn't interfere with a
pipelined request, we can remove the forced `Connection: close` that was
added to force clients to establish a new connection.
The Go timestamp leads Truncate to start a week on Monday, but the query
engine uses unix timestamps which has the week start on a Thursday.
Updating the service so it uses a custom truncate method that uses the
unix timestamp instead of `time.Time`.
Fixes#8569.
This commit adds a new environment variable INFLUXDB_PANIC_CRASH, which
when set to a truthy value, e.g., true, TRUE, 1, will prevent the server
from recovering from a panic.
Recover currently occurs in two places: the HTTP handler and the
QueryExecutor. INFLUXDB_PANIC_CRASH will control both.
Further, this commit adds _internal stats that will monitor the
occurrence of panics all the time (regardless of if INFLUXDB_PANIC_CRASH
has been set to true or not).
The recovered panic frequency can be inspected with the following
queries:
SELECT "recoveredPanics" FROM "_internal"."monitor"."httpd";
SELECT "recoveredPanics" FROM "_internal"."monitor"."queryExecutor";
* off by default, enabled by `query-stats-enabled`
* writes to cq_query measurement of configured monitor database
* see CHANGELOG for schema of individual points
* fix issue when panicking (before Write) gzip writer is closed, causing
header to be written and default status of 200 OK being written.
* update recovery middleware to set 500 Internal Server Error
Edd Robinson
Stuart Carnie
Jonathan A. Sternberg
Byungjin Park
Mark Rushakoff
Paul Dix
Joe LeGasse
Jonathan Heusser
Connor Peet
Adam
Ryan Betts