This is implemented so that the issues like in the
following flow don't affect the behavior of operation.
```
GetObjectInfo()
.... --> Time window for mutation (no lock held)
.... --> Time window for mutation (no lock held)
GetObject()
```
This happens when two simultaneous uploads are made
to the same object the object has returned wrong
info to the client.
Another classic example is "CopyObject" API itself
which reads from a source object and copies to
destination object.
Fixes#3370Fixes#2912
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
- abstract out instrumentation information.
- use separate lockInstance type that encapsulates the nsMutex, volume,
path and opsID as the frontend or top-level lock object.
- Instrumentation for locks.
- Detailed test coverage.
- Adding RPC control handler to fetch lock instrumentation.
- RPC control handlers suite tests with a test RPC server.
* Implement basic S3 notifications through queues
Supports multiple queues and three basic queue types:
1. NilQueue -- messages don't get sent anywhere
2. LogQueue -- messages get logged
3. AmqpQueue -- messages are sent to an AMQP queue
* api: Implement bucket notification.
Supports two different queue types
- AMQP
- ElasticSearch.
* Add support for redis
The reason is any function relying on `getLoadBalancedQuorumDisks`
cannot possibly have an idempotent behavior.
The problem comes from given a set of N disks returning just a
shuffled N/2 disks. In case of a scenario where we have N/2
number of failed disks, the returned value of `getLoadBalancedQuorumDisks`
is not equal to the same failed disks so essentially calls using such
disks might succeed or fail randomly at different intervals in time.
This proposal change is we move to `getLoadBalancedDisks()`
and use the shuffled N disks as a whole. Since most of the time we might
hit a good disk since we are not reducing our solution space. This
also provides consistent behavior for all the functions which rely
on shuffled disks.
Fixes#2242
Each metadata ops have a list of errors which can be
ignored, this is essentially needed when
- disks are not found
- disks are found but cannot be accessed (permission denied)
- disks are there but fresh disks were added
This is needed since we don't have healing code in place where
it would have healed the fresh disks added.
Fixes#2072