This is a minor cosmetical change, but my IDE (and I guess many of them)
nests `labels_string.go` under `labels.go` because it assumes it's the
file generated by the `stringer` tool, which follows that naming
pattern.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
labels: dont compile regex matcher if we know its a literal
Signed-off-by: Michael Hoffmann <mhoffm@posteo.de>
Co-authored-by: Sharad <sharadgaur@gmail.com>
Inline one call to `decodeString`, and skip decoding the value string
until we find a match for the name.
Do a quick check on the first character in each string,
and exit early if we've gone past - labels are sorted in order.
Also improve tests and benchmark:
* labels: test Get with varying lengths - it's not typical for Prometheus labels to all be the same length.
* extend benchmark with label not found
---------
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Instead of unpacking every individual string, we skip to the point
where there is a difference, going 8 bytes at a time where possible.
Add benchmark for Compare; extend tests too.
---------
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Co-authored-by: Oleg Zaytsev <mail@olegzaytsev.com>
Inline one call to `decodeString`, and skip decoding the value string
until we find a match for the name.
Do a quick check on the first character in each string,
and exit early if we've gone past - labels are sorted in order.
Also improve tests and benchmark:
* labels: test Get with varying lengths - it's not typical for Prometheus labels to all be the same length.
* extend benchmark with label not found
---------
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Instead of unpacking every individual string, we skip to the point
where there is a difference, going 8 bytes at a time where possible.
Add benchmark for Compare; extend tests too.
---------
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Co-authored-by: Oleg Zaytsev <mail@olegzaytsev.com>
This is a minor cosmetical change, but my IDE (and I guess many of them)
nests `labels_string.go` under `labels.go` because it assumes it's the
file generated by the `stringer` tool, which follows that naming
pattern.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
labels: dont compile regex matcher if we know its a literal
Signed-off-by: Michael Hoffmann <mhoffm@posteo.de>
Co-authored-by: Sharad <sharadgaur@gmail.com>
* labels: respect Set after Del in Builder
The implementations are not symmetric between `Set()` and `Del()`, so
we must be careful. Add tests for this, both in labels and in relabel
where the issue was reported.
Also make the slice implementation consistent re `slices.Contains`.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Wiser coders than myself have come to the conclusion that a `switch`
statement is almost always superior to a statement that includes any
`else if`.
The exceptions that I have found in our codebase are just these two:
* The `if else` is followed by an additional statement before the next
condition (separated by a `;`).
* The whole thing is within a `for` loop and `break` statements are
used. In this case, using `switch` would require tagging the `for`
loop, which probably tips the balance.
Why are `switch` statements more readable?
For one, fewer curly braces. But more importantly, the conditions all
have the same alignment, so the whole thing follows the natural flow
of going down a list of conditions. With `else if`, in contrast, all
conditions but the first are "hidden" behind `} else if `, harder to
spot and (for no good reason) presented differently from the first
condition.
I'm sure the aforemention wise coders can list even more reasons.
In any case, I like it so much that I have found myself recommending
it in code reviews. I would like to make it a habit in our code base,
without making it a hard requirement that we would test on the CI. But
for that, there has to be a role model, so this commit eliminates all
`if else` occurrences, unless it is autogenerated code or fits one of
the exceptions above.
Signed-off-by: beorn7 <beorn@grafana.com>
* Limit FastRegexMatcher by size (bytes) and add a TTL to each entry
Signed-off-by: Marco Pracucci <marco@pracucci.com>
* Add TestNewFastRegexMatcher_CacheSizeLimit
Signed-off-by: Marco Pracucci <marco@pracucci.com>
* Tolerate ristretto goroutines when checking goroutine leaks
Signed-off-by: Marco Pracucci <marco@pracucci.com>
* Tolerate ristretto goroutines when checking goroutine leaks
Signed-off-by: Marco Pracucci <marco@pracucci.com>
---------
Signed-off-by: Marco Pracucci <marco@pracucci.com>
Add a fast path for the common case that a string is less than 127 bytes
long, to skip a shift and the loop.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
This is a method used by some downstream projects; it was created to
optimize the implementation in `labels_string.go` but we should have one
for both implementations so the same code works with either.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Deleted labels are remembered, even if they were not in `base` or were
removed from `add`, so `base+add-del` could go negative.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Use a prefix trie for long alternate lists
* Add test for non terminal node
* Fix panic in FuzzFastRegexMatcher_WithFuzzyRegularExpressions when the fuzzy regex is invalid
Signed-off-by: Marco Pracucci <marco@pracucci.com>
* Address PR feedback
* Update model/labels/regexp_test.go
Co-authored-by: Marco Pracucci <marco@pracucci.com>
* Replace trie with slice or map depending on input size
* Fix tests
* Pull in tests from @pracucci's branch
* Add setMatches back in
* Use stringMatcher when it's faster
* Fix linter
* Estimate alternates ahead of time
* Simplify construction with `IndexByte`
* Add test and early return for empty regexp.
* Fix race conditions in tests
---------
Signed-off-by: Marco Pracucci <marco@pracucci.com>
Co-authored-by: Marco Pracucci <marco@pracucci.com>
Go spends some time initializing all the elements of these arrays to
zero, so reduce the size from 1024 to 128. This is still much bigger
than we ever expect for a set of labels.
(If someone does have more than 128 labels it will still work, but via
heap allocation.)
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
It took a `Labels` where the memory could be re-used, but in practice
this hardly ever benefitted. Especially after converting `relabel.Process`
to `relabel.ProcessBuilder`.
Comparing the parameter to `nil` was a bug; `EmptyLabels` is not `nil`
so the slice was reallocated multiple times by `append`.
Lastly `Builder.Labels()` now estimates that the final size will depend
on labels added and deleted.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Although we had a different slice, the underlying memory was the same so
any changes meant we could skip some values.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
