```
minio[1032735]: panic: label value "\xc0.\xc0." is not valid UTF-8
minio[1032735]: goroutine 1781101 [running]:
minio[1032735]: github.com/prometheus/client_golang/prometheus.MustNewConstMetric(...)
```
log such errors for investigation
Send() is synchronous and can affect the latency of S3 requests when the
logger buffer is full.
Avoid checking if the HTTP target is online or not and increase the
workers anyway since the buffer is already full.
Also, avoid logs flooding when the audit target is down.
Limit large uploads (> 128MiB) to a max of 10 workers, intent is to avoid
larger uploads from using all replication bandwidth, giving room for smaller
uploads to sync faster.
slower drives get knocked off because they are too slow via
active monitoring, we do not need to block calls arbitrarily.
Serializing adds latencies for already slow calls, remove
it for SSDs/NVMEs
Also, add a selection with context when writing to `out <-`
channel, to avoid any potential blocks.
Revert "don't error when asked for 0-based range on empty objects (#17708)"
This reverts commit 7e76d66184.
There is no valid way to specify offsets in a 0-byte file. Blame it on the [RFC](https://datatracker.ietf.org/doc/html/rfc7233#section-4.4)
> The 416 (Range Not Satisfiable) status code indicates that none of the ranges in the
> request's Range header field (Section 3.1) overlap the current extent of the selected resource...
A request for "bytes=0-" is a request for the first byte of a resource. If the resource is 0-length,
the range [0,0] does not overlap the resource content and the server responds with an error.
In a reverse proxying setup, a proxy in front of MinIO may attempt to
request objects in slices for enhanced cache efficiency. Since such a
a proxy cannot have prior knowledge of how large a requested resource is,
it usually sends a header of the form:
Range: 0-$slice_size
... and, depending on the size of the resource, expects either:
- an empty response, if $resource_size == 0
- a full response, if $resource_size <= $slice_size
- a partial response, if $resource_size > $slice_size
Prior to this change, MinIO would respond 416 Range Not Satisfiable if a
client tried to request a range on an empty resource. This behavior is
technically consistent with RFC9110[1] – However, it renders sliced
reverse proxying, such as implemented in Nginx, broken in the case of
empty files. Nginx itself seems to break this convention to enable
"useful" responses in these cases, and MinIO should probably do that
too.
[1]: https://www.rfc-editor.org/rfc/rfc9110#byte.ranges
sending whitespace character with CompleteMultipartUpload()
with 200 OK was an AWS S3 compatible implementation detail,
and it was expected that the client SDK must look for both
successful XML as well as error XML for 200 OK.
But this is not useful anymore on MinIO, since we do not
have any large delayed coalescing of parts anymore.
users/customers do not have a reasonable number of buckets anymore,
this is why we must avoid overpopulating cluster endpoints, instead
move the bucket monitoring to a separate endpoint.
some of it's a breaking change here for a couple of metrics, but
it is imperative that we do it to improve the responsiveness of
our Prometheus cluster endpoint.
Bonus: Added new cluster metrics for usage, objects and histograms
