Optionally allows customers to enable
- Enable an external cache to catch GET/HEAD responses
- Enable skipping disks that are slow to respond in GET/HEAD
when we have already achieved a quorum
globalDeploymentID was being read while it was being set.
Fixes race:
```
WARNING: DATA RACE
Write at 0x0000079605a0 by main goroutine:
github.com/minio/minio/cmd.connectLoadInitFormats()
github.com/minio/minio/cmd/prepare-storage.go:269 +0x14f0
github.com/minio/minio/cmd.waitForFormatErasure()
github.com/minio/minio/cmd/prepare-storage.go:294 +0x21d
...
Previous read at 0x0000079605a0 by goroutine 105:
github.com/minio/minio/cmd.newContext()
github.com/minio/minio/cmd/utils.go:817 +0x31e
github.com/minio/minio/cmd.adminMiddleware.func1()
github.com/minio/minio/cmd/admin-router.go:110 +0x96
net/http.HandlerFunc.ServeHTTP()
net/http/server.go:2136 +0x47
github.com/minio/minio/cmd.setBucketForwardingMiddleware.func1()
github.com/minio/minio/cmd/generic-handlers.go:460 +0xb1a
net/http.HandlerFunc.ServeHTTP()
net/http/server.go:2136 +0x47
...
```
batch status can perpetually wait after completion
due to a race between the MetricsHandler() returning
the active metrics in intervals of 1sec and delete
of metrics after job completion.
this PR ensures that we keep the 'status' around
for a while, i.e upto 24hrs for all the batch jobs.
health checks were missing for drives replaced since
- HealFormat() would replace the drives without a health check
- disconnected drives when they reconnect via connectEndpoint()
the loop also loses health checks for local disks and merges
these into a single code.
- other than this separate cleanUp, health check variables to avoid
overloading them with similar requirements.
- also ensure that we compete via context selector for disk monitoring
such that the canceled disks don't linger around longer waiting for
the ticker to trigger.
- allow disabling active monitoring.
DNS refresh() in-case of MinIO can safely re-use
the previous values on bare-metal setups, since
bare-metal arrangements do not change DNS in any
manner commonly.
This PR simplifies that, we only ever need DNS caching
on bare-metal setups.
- On containerized setups do not enable DNS
caching at all, as it may have adverse effects on
the overall effectiveness of k8s DNS systems.
k8s DNS systems are dynamic and expect applications
to avoid managing DNS caching themselves, instead
provide a cleaner container native caching
implementations that must be used.
- update IsDocker() detection, including podman runtime
- move to minio/dnscache fork for a simpler package
It is observed in a local 8 drive system the CPU seems to be
bottlenecked at
```
(pprof) top
Showing nodes accounting for 1385.31s, 88.47% of 1565.88s total
Dropped 1304 nodes (cum <= 7.83s)
Showing top 10 nodes out of 159
flat flat% sum% cum cum%
724s 46.24% 46.24% 724s 46.24% crypto/sha256.block
219.04s 13.99% 60.22% 226.63s 14.47% syscall.Syscall
158.04s 10.09% 70.32% 158.04s 10.09% runtime.memmove
127.58s 8.15% 78.46% 127.58s 8.15% crypto/md5.block
58.67s 3.75% 82.21% 58.67s 3.75% github.com/minio/highwayhash.updateAVX2
40.07s 2.56% 84.77% 40.07s 2.56% runtime.epollwait
33.76s 2.16% 86.93% 33.76s 2.16% github.com/klauspost/reedsolomon._galMulAVX512Parallel84
8.88s 0.57% 87.49% 11.56s 0.74% runtime.step
7.84s 0.5% 87.99% 7.84s 0.5% runtime.memclrNoHeapPointers
7.43s 0.47% 88.47% 22.18s 1.42% runtime.pcvalue
```
Bonus changes:
- re-use transport for bucket replication clients, also site replication clients.
- use 32KiB buffer for all read and writes at transport layer seems to help
TLS read connections.
- Do not have 'MaxConnsPerHost' this is problematic to be used with net/http
connection pooling 'MaxIdleConnsPerHost' is enough.