Previously the /service-discovery page didn't show targets dropped because of sharding
( https://docs.victoriametrics.com/vmagent.html#scraping-big-number-of-targets ).
Show also the reason why every target is dropped at /service-discovery page.
This should improve debuging why particular targets are dropped.
While at it, do not remove dropped targets from the list at /service-discovery page
until the total number of targets exceeds the limit passed to -promscrape.maxDroppedTargets .
Previously the list was cleaned up every 10 minutes from the entries, which weren't updated
for the last minute. This could complicate debugging of dropped targets.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5389
- Improve docs
- Hide `debug relabeling` column when -promscrape.dropOriginalLabels command-line flag is set
- Inline the code from the added template functions, since the code is harder to follow
with the template functions, especially when these functions have misleading names.
Also, these functions are used only in one place, e.g. they do not reduce the amounts of code.
- Hide `click to show original labels` title at `labels` column when original labels aren't available.
- Show the reason on whey original labels aren't available at /service-discovery page.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4597
* app/vmagent: fix creating target id if `--promscrape.dropOriginalLabels` flag was used
* app/vmagent: hide links if OriginalLabels was dropped
* app/vmagent: update CHANGELOG.md and added information to the docs
* app/vmagent: fix comments
- Return meta-labels for the discovered targets via promutils.Labels
instead of map[string]string. This improves the speed of generating
meta-labels for discovered targets by up to 5x.
- Remove memory allocations in hot paths during ScrapeWork generation.
The ScrapeWork contains scrape settings for a single discovered target.
This improves the service discovery speed by up to 2x.
- Remove unused js bloatware from /targets page. This strips down binary size by more than 100Kb
- Add /service-discovery page for API compatibility with Prometheus
- Properly load bootstrap.min.css from /prometheus/targets
- Serve static contents for /targets page from app/vminsert instead of app/vmselect, because /targets page is served from there
