At a customer setup with lots of concurrent calls
it can be observed that in newRetryTimer there
were lots of tiny alloations which are not
relinquished upon retries, in this codepath
we were only interested in re-using the timer
and use it wisely for each locker.
```
(pprof) top
Showing nodes accounting for 8.68TB, 97.02% of 8.95TB total
Dropped 1198 nodes (cum <= 0.04TB)
Showing top 10 nodes out of 79
flat flat% sum% cum cum%
5.95TB 66.50% 66.50% 5.95TB 66.50% time.NewTimer
1.16TB 13.02% 79.51% 1.16TB 13.02% github.com/ncw/directio.AlignedBlock
0.67TB 7.53% 87.04% 0.70TB 7.78% github.com/minio/minio/cmd.xlObjects.putObject
0.21TB 2.36% 89.40% 0.21TB 2.36% github.com/minio/minio/cmd.(*posix).Walk
0.19TB 2.08% 91.49% 0.27TB 2.99% os.statNolog
0.14TB 1.59% 93.08% 0.14TB 1.60% os.(*File).readdirnames
0.10TB 1.09% 94.17% 0.11TB 1.25% github.com/minio/minio/cmd.readDirN
0.10TB 1.07% 95.23% 0.10TB 1.07% syscall.ByteSliceFromString
0.09TB 1.03% 96.27% 0.09TB 1.03% strings.(*Builder).grow
0.07TB 0.75% 97.02% 0.07TB 0.75% path.(*lazybuf).append
```
Too many deployments come up with an odd number
of hosts or drives, to facilitate even distribution
among those setups allow for odd and prime numbers
based packs.
Change distributed locking to allow taking bulk locks
across objects, reduces usually 1000 calls to 1.
Also allows for situations where multiple clients sends
delete requests to objects with following names
```
{1,2,3,4,5}
```
```
{5,4,3,2,1}
```
will block and ensure that we do not fail the request
on each other.
Use reference format to initialize lockers
during startup, also handle `nil` for NetLocker
in dsync and remove *errorLocker* implementation
Add further tuning parameters such as
- DialTimeout is now 15 seconds from 30 seconds
- KeepAliveTimeout is not 20 seconds, 5 seconds
more than default 15 seconds
- ResponseHeaderTimeout to 10 seconds
- ExpectContinueTimeout is reduced to 3 seconds
- DualStack is enabled by default remove setting
it to `true`
- Reduce IdleConnTimeout to 30 seconds from
1 minute to avoid idleConn build up
Fixes#8773
This PR implements locking from a global entity into
a more localized set level entity, allowing for locks
to be held only on the resources which are writing
to a collection of disks rather than a global level.
In this process this PR also removes the top-level
limit of 32 nodes to an unlimited number of nodes. This
is a precursor change before bring in bucket expansion.
Harshavardhana