This change corrects a bug introduced by PR
https://github.com/prometheus/prometheus/pull/2427
The regex uses three groups: the hostname, an optional port, and the
prefered port from a kubernetes annotation.
Previously, the second group should have been ignored if a :port was not
present in the input. However, making the port group optional with the
"?" had the unintended side-effect of allowing the hostname regex "(.+)"
to match greedily, which included the ":port" patterns up to the ";"
separating the hostname from the kubernetes port annotation.
This change updates the regex for the hostname to match any non-":"
characters. This forces the regex to stop if a ":port" is present and
allow the second group to match the optional port.
This change updates port relabeling for pod and service discovery so the
relabeling regex matches addresses with or without declared ports. As
well, this change uses a consistent style in the replacement pattern
for the two expressions.
Previously, for both services or pods that did not have declared ports, the
relabel config regex would fail to match:
__meta_kubernetes_service_annotation_prometheus_io_port
regex: (.+)(?::\d+);(\d+)
__meta_kubernetes_pod_annotation_prometheus_io_port
regex: (.+):(?:\d+);(\d+)
Both regexes expected a <host>:<port> pattern.
The new regex matches addresses with or without declared ports by making
the :<port> pattern optional.
__meta_kubernetes_service_annotation_prometheus_io_port
__meta_kubernetes_pod_annotation_prometheus_io_port
regex: (.+)(?::\d+)?;(\d+)
This removes legacy support for specific remote storage systems in favor
of only offering the generic remote write protocol. An example bridge
application that translates from the generic protocol to each of those
legacy backends is still provided at:
documentation/examples/remote_storage/remote_storage_bridge
See also https://github.com/prometheus/prometheus/issues/10
The next step in the plan is to re-add support for multiple remote
storages.
This is another corner-case that was previously never exercised
because the rewriting of a series file was never prevented by the
shrink ratio.
Scenario: There is an existing series on disk, which is archived. If a
new sample comes in for that file, a new chunk in memory is created,
and the chunkDescsOffset is set to -1. If series maintenance happens
before the series has at least one chunk to persist _and_ an
insufficient chunks on disk is old enough for purging (so that the
shrink ratio kicks in), dropAndPersistChunks would return 0, but it
should return the chunk length of the series file.
Also, in that code path, set chunkDescsOffset to 0 rather than -1 in
case of "dropped more chunks from persistence than from memory" so
that no other weird things happen before the series is quarantined for
good.
The append call may reuse cds, and thus change its len.
(In practice, this wouldn't happen as cds should have len==cap.
Still, the previous order of lines was problematic.)
In preparation for removing specific remote storage implementations,
this offers an example of how to achieve the same in a separate process.
Rather than having three separate bridges for OpenTSDB, InfluxDB, and
Graphite, I decided to support all in one binary.
For now, this is in the example documenation directory, but perhaps we
will want to make a first-class project / repository out of it.
