This is needed as explained by @krisis
Lets say we have following errors.
```
[]error{nil, errFileNotFound, errDiskAccessDenied, errDiskAccesDenied}
```
Since the last two errors are filtered, the maximum is nil,
depending on map order.
Let's say we get nil from reduceErr. Clearly at this point
we don't have quorum nodes agreeing about the data and since
GetObject only requires N/2 (Read quorum) and isDiskQuorum
would have returned true. This is problematic and can lead to
undersiable consequences.
Fixes#3298
Disks when are offline for a long period of time, we should
ignore the disk after trying Login upto 5 times.
This is to reduce the network chattiness, this also reduces
the overall time spent on `net.Dial`.
Fixes#3286
- Using gjson for constructing xlMetaV1{} in realXLMeta.
- Test for parsing constructing xlMetaV1{} using gjson.
- Changes made since benchmarks showed 30-40% improvement in speed.
- Follow up comments in issue https://github.com/minio/minio/issues/2208
for more details.
- gjson parsing of parts from xl.json for listParts.
- gjson parsing of statInfo from xl.json for getObjectInfo.
- Vendorizing gjson dependency.
* XL: Refactor xl.GetObject and erasureReadFile. erasureReadFile() responsible for just erasure coding, it takes ordered disks and checkSum slice.
* move getOrderedPartsMetadata and getOrderedDisks to xl-v1-utils.go
* Review fixes.
This change is needed to make reading from objects future proof
in-terms of handling online disks. Our current counter is not
based on affirmative knowledge and relies on arithmetic sequence
which can lead to bugs.
Using modTime simplifies the understanding of `xl.json` and future
tooling / debugging of the format.
* xl/selfheal: selfheal based on read quorum on GET
* xl: getReadableDisks() also returns whether self-heal is needed so that this info can be used by ReadFile/SelfHeal/StatFile.
* xl: trigger selfheal from StatFile.
Krishnan Parthasarathi