Currently, when debugging issues with InfluxDB we often ask for the
following profiles:
curl -o block.txt "http://localhost:8086/debug/pprof/block?debug=1"
curl -o goroutine.txt
"http://localhost:8086/debug/pprof/goroutine?debug=1"
curl -o heap.txt "http://localhost:8086/debug/pprof/heap?debug=1"
curl -o cpu.txt "http://localhost:8086/debug/pprof/profile
This can be bothersome for users, or even difficult if they're
unfamiliar with cURL (or it's not on their system).
This commit adds a new endpoint: /debug/pprof/all which will return a
single compressed archive of all of the above profiles. The CPU profile
is optional, and not returned by default. To include a CPU profile the
URL to request should be: /debug/pprof/all?cpu=true. It's also possible
to vary the length of the CPU profile by adding a `seconds=x` parameter,
where x defaults to 30, if absent.
The new command for gathering profiles from users should now be:
curl -o profiles.tar.gz "http://localhost:8086/debug/pprof/all"
Or, if we need to see a CPU profile:
curl -o profiles.tar.gz
"http://localhost:8086/debug/pprof/all?cpu=true"
It's important to remember that a CPU profile is a blocking operation
and by default it will take 30 seconds for the response to be returned
to the user.
Finally, if the user is unfamiliar with cURL, they will now be able to
visit http://localhost:8086/debug/pprof/all in a web browser, and the
archive will be downloaded to their machine.
This changes full compactions within a shard to run sequentially
instead of running all the compaction groups in parallel. Normally,
there is only 1 full compaction group to run. At times, there could
be several which causes instability if they are all running concurrently
as they tie up a cpu for long periods of time.
Level compactions are also capped to a max of 4 concurrently running for each level
in a shard. This prevents sudden spikes in CPU and disk usage due to a large backlog
of tsm files at a given level.
Measurement name and field were converted between []byte and string
repetively causing lots of garbage. This switches the code to use
[]byte in the write path.
This pool was previously a pool.Bytes to avoid repetitive allocations.
It was recently switchted to a sync.Pool because pool.Bytes held onto
very larger buffers at times which were never released. sync.Pool is
showing up in allocation profiles quite frequently.
This switches the pool to a new pool that limits how many buffers are
in the pool as well as the max size of each buffer in the pool. This
provides better bounds on allocations.
This speeds up time encoding and decoding by skipping the divisor
scaling if scaling by 1. Since division and multiplication are expensive
cpu and scaling by 1 has no effect, this just slows encoding and decoding
down.
After using `/debug/requests`, the client will wait for 30 seconds
(configurable by specifying `seconds=` in the query parameters) and the
HTTP handler will track every incoming query and write to the system.
After that time period has passed, it will output a JSON blob that looks
very similar to `/debug/vars` that shows every IP address and user
account (if authentication is used) that connected to the host during
that time.
In the future, we can add more metrics to track. This is an initial
start to aid with debugging machines that connect too often by looking
at a sample of time (like `/debug/pprof`).
Tombstone files would be written to all TSM files even if the deleted
keys or timerange did not exist in the TSM file. This had the side
effect of causing shards to get recompacted back to the same state. If
any shards or large numbers of TSM files existed, disk usage and CPU
utilization would spike causing issues.
This prevents tombstones being written for TSM files that could not
possiby contain the series keys being deleted or if the delted time
range is outside the range of the file.
When monitoring shards, a slice of measurements is allocated for
each shard. With many shards and measurements, these allocations
can be large. Since inmem shards share the same index, we only
need to do this once since the resulting slices are all the same.
This reduces memory usage when monitoring shard cardinality.
Since this is called more frequently now, the cleanup func was invoked
quite a bit which makes several syscalls per shard. This should only
be called the first time compactions are disabled.
Index.ForEachMeasurementTagKey held an RLock while call the fn,
if the fn made another call into the index which acquired an RLock
and after another goroutine tried to acquire a Lock, it would deadlock.
Jason Wilder
Mark Rushakoff
Edd Robinson
Mark Rushakoff
Jason Wilder
Stuart Carnie
Joe LeGasse
Jonathan A. Sternberg
Sebastian Borza
Ben Johnson
rw-influxdata