on "unversioned" buckets there are situations
when successive concurrent I/O can lead to
an inconsistent state() with mtime while the
etag might be the same for the object on disk.
in such a scenario it is possible for us to
allow reading of the object since etag matches
and if etag matches we are guaranteed that we
have enough copies the object will be readable
and same.
This PR allows fallback in such scenarios.
This PR changes the handling of bucket deletes for site
replicated setups to hold on to deleted bucket state until
it syncs to all the clusters participating in site replication.
FileInfo quorum shouldn't be passed down, instead
inferred after obtaining a maximally occurring FileInfo.
This PR also changes other functions that rely on
wrong quorum calculation.
Update tests as well to handle the proper requirement. All
these changes are needed when migrating from older deployments
where we used to set N/2 quorum for reads to EC:4 parity in
newer releases.
dataDir loosely based on maxima is incorrect and does not
work in all situations such as disks in the following order
- xl.json migration to xl.meta there may be partial xl.json's
leftover if some disks are not yet connected when the disk
is yet to come up, since xl.json mtime and xl.meta is
same the dataDir maxima doesn't work properly leading to
quorum issues.
- its also possible that XLV1 might be true among the disks
available, make sure to keep FileInfo based on common quorum
and skip unexpected disks with the older data format.
Also, this PR tests upgrade from older to a newer release if the
data is readable and matches the checksum.
NOTE: this is just initial work we can build on top of this to do further tests.
there is a corner case where the new check
doesn't work where dataDir has changed, especially
when xl.json -> xl.meta healing happens, if some
healing is partial this can make certain backend
files unreadable.
This PR fixes and updates unit-tests
- remove some duplicated code
- reported a bug, separately fixed in #13664
- using strings.ReplaceAll() when needed
- using filepath.ToSlash() use when needed
- remove all non-Go style comments from the codebase
Co-authored-by: Aditya Manthramurthy <donatello@users.noreply.github.com>
DeleteMarkers were unreadable if they had quorum based
guarantees, this PR tries to fix this behavior appropriately.
DeleteMarkers with sufficient should be allowed and the
return error should be accordingly with or without version-id.
This also allows for overwrites which may not be possible
in a multi-pool setup.
fixes#12787
* fix: pick valid FileInfo additionally based on dataDir
historically we have always relied on modTime
to be consistent and same, we can now add additional
reference to look for the same dataDir value.
A dataDir is the same for an object at a given point in
time for a given version, let's say a `null` version
is overwritten in quorum we do not by mistake pick
up the fileInfo's incorrectly.
* make sure to not preserve fi.Data
Signed-off-by: Harshavardhana <harsha@minio.io>
This PR refactors the way we use buffers for O_DIRECT and
to re-use those buffers for messagepack reader writer.
After some extensive benchmarking found that not all objects
have this benefit, and only objects smaller than 64KiB see
this benefit overall.
Benefits are seen from almost all objects from
1KiB - 32KiB
Beyond this no objects see benefit with bulk call approach
as the latency of bytes sent over the wire v/s streaming
content directly from disk negate each other with no
remarkable benefits.
All other optimizations include reuse of msgp.Reader,
msgp.Writer using sync.Pool's for all internode calls.
Design: https://gist.github.com/klauspost/025c09b48ed4a1293c917cecfabdf21c
Gist of improvements:
* Cross-server caching and listing will use the same data across servers and requests.
* Lists can be arbitrarily resumed at a constant speed.
* Metadata for all files scanned is stored for streaming retrieval.
* The existing bloom filters controlled by the crawler is used for validating caches.
* Concurrent requests for the same data (or parts of it) will not spawn additional walkers.
* Listing a subdirectory of an existing recursive cache will use the cache.
* All listing operations are fully streamable so the number of objects in a bucket no
longer dictates the amount of memory.
* Listings can be handled by any server within the cluster.
* Caches are cleaned up when out of date or superseded by a more recent one.
Add context to all (non-trivial) calls to the storage layer.
Contexts are propagated through the REST client.
- `context.TODO()` is left in place for the places where it needs to be added to the caller.
- `endWalkCh` could probably be removed from the walkers, but no changes so far.
The "dangerous" part is that now a caller disconnecting *will* propagate down, so a
"delete" operation will now be interrupted. In some cases we might want to disconnect
this functionality so the operation completes if it has started, leaving the system in a cleaner state.
- Implement a new xl.json 2.0.0 format to support,
this moves the entire marshaling logic to POSIX
layer, top layer always consumes a common FileInfo
construct which simplifies the metadata reads.
- Implement list object versions
- Migrate to siphash from crchash for new deployments
for object placements.
Fixes#2111
Aditya Manthramurthy
Harshavardhana
Krishnan Parthasarathi
Anis Elleuch
ebozduman
Poorna
Praveen raj Mani
Klaus Post