RequestScope is a large struct and causes stack growth when we pass
it by value into multiple stack levels. Avoid the allocations for
this read only struct by passing a pointer.
Kubernetes-commit: 8fede0b18a81a6fb1acc1a48857f482857c25286
A self link should only require one allocation, and we should skip
url.PathEscape() except when the path actually needs it.
Add a fuzz test to build random strings and verify them against
the optimized implementation. Add a new BenchmarkWatchHTTP_UTF8 that
covers when we have unicode names in the self link.
```
> before
BenchmarkGet-12 10000 118863 ns/op 17482 B/op 130 allocs/op
BenchmarkWatchHTTP-12 30000 38346 ns/op 1893 B/op 29 allocs/op
> after
BenchmarkGet-12 10000 116218 ns/op 17456 B/op 130 allocs/op
BenchmarkWatchHTTP-12 50000 35988 ns/op 1571 B/op 26 allocs/op
BenchmarkWatchHTTP_UTF8-12 50000 41467 ns/op 1928 B/op 28 allocs/op
```
Saves 3 allocations in the fast path and 1 in the slow path (the
slow path has to build the buffer and then call url.EscapedPath
which always allocates).
Kubernetes-commit: 389a8436b52db4936b56e08f07984da362c91f6b
There was no reason to have two types and this avoids ~10% of allocations
on the GET code path.
```
BenchmarkGet-12 100000 109045 ns/op 17608 B/op 146 allocs/op
BenchmarkGet-12 100000 108850 ns/op 15942 B/op 132 allocs/op
```
Kubernetes-commit: 0489d0b1cf139253b82f73b072578073bc5616d6
ReplaceAllStrings always allocates, while scanning a relatively short
regex twice is slightly more CPU immediately but less later.
```
BenchmarkGet-12 100000 108824 ns/op 17818 B/op 152 allocs/op
BenchmarkGet-12 100000 108013 ns/op 17732 B/op 149 allocs/op
```
Kubernetes-commit: 83c41eab1d6f55c9ccf61744bfc345c95d3a0664
IsListType was causing ~100 allocations for a non list object. It is
used in a wide range of code, so perform a more targeted check.
The use of `%#v` in a hot return path for `fmt.Errorf()` was the main
victim.
Replace `%#v` with a typed error and create a cache of types that are
lists with a bounded size (probably not necessary, but safer).
```
BenchmarkGet-12 100000 119635 ns/op 20110 B/op 206 allocs/op
BenchmarkWatchHTTP-12 100000 65761 ns/op 7296 B/op 139 allocs/op
BenchmarkGet-12 100000 109085 ns/op 17831 B/op 152 allocs/op
BenchmarkWatchHTTP-12 200000 33966 ns/op 1913 B/op 30 allocs/op
```
Kubernetes-commit: 58fb665646aa4c1b63f1322a50e3af7a60e39886
UUIDv1 has several disadvantages:
- it encodes the MAC address of the host, which is a potential privacy issue
- it uses the clock of the host, which reveals time information
- the clock is very coarse, hence the complex code handling duplicates
UUIDv4 is simply a 122 bit random number encoded into the UUID format, which
has no problems with duplicates or locking.
Use the google/uuid library, as newer versions of pborman/uuid just wrap the
Google upstream.
Note that technically a random UUID might fail, but Go ensures that this
should not take place, as it will block if entropy is not available.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
Kubernetes-commit: 0fb4b81c3f5139d09208b63a62574d0eb85e0390
Service account authorization checks are done frequently and were
observed to perform 7% of allocations on a system running e2e tests.
The allocation comes from when we walk the authorization rules to
find matching service accounts.
Optimize the check for service account names to avoid allocating.
Kubernetes-commit: 4c87a14e6b1809359fcb6566d883a169ff0db259
What is the problem being solved?
https://github.com/kubernetes/kubernetes/pull/75135
Currently version compatibility is not being checked in server side apply between the patch object and the live object. This is causing a merge that will error to be run and the apiserver returns a 500 error. The request should fail if the apiVersion provided in the object is different from the apiVersion in the url, but it should fail before trying to merge, and be a 4xx error. Probably a bad request error.
Why is this the best approach?
The approach of serializing the patch byte array and then checking for version equality with the already serialized live object is the simplest and most straightforward solution.
Kubernetes-commit: d5bd17cda0c134e5ef5c03c3eac79a9ce4e18003
And add a corresponding flag in kubectl (for apply), even though the
value is defaulted in kubectl with "kubectl".
The flag is required for Apply patch-type, and optional for other PATCH,
CREATE and UPDATE (in which case we fallback on the user-agent).
Kubernetes-commit: eb904d8fa89da491f400614f99458ed3f0d529fb