xl.meta gets written and never rolled back, however
we definitely need to validate the state that is
persisted on the disk, if there are inconsistencies
- more than write quorum we should return an error
to the client
- if write quorum was achieved however there are
inconsistent xl.meta's we should simply trigger
an MRF on them
inlined data often is bigger than the allowed
O_DIRECT alignment, so potentially we can write
'xl.meta' without O_DSYNC instead we can rely on
O_DIRECT + fdatasync() instead.
This PR allows O_DIRECT on inlined data that
would gain the benefits of performing O_DIRECT,
eventually performing an fdatasync() at the end.
Performance boost can be observed here for small
objects < 128KiB. The performance boost is mainly
seen on HDD, and marginal on NVMe setups.
a/b/c/d/ where `a/b/c/` exists results in additional syscalls
such as an Lstat() call to verify if the `a/b/c/` exists
and its a directory.
We do not need to do this on MinIO since the parent prefixes
if exist, we can simply return success without spending
additional syscalls.
Also this implementation attempts to simply use Access() calls
to avoid os.Stat() calls since the latter does memory allocation
for things we do not need to use.
Access() is simpler since we have a predictable structure on
the backend and we know exactly how our path structures are.
Do completely independent multipart uploads.
In distributed mode, a lock was held to merge each multipart
upload as it was added. This lock was highly contested and
retries are expensive (timewise) in distributed mode.
Instead, each part adds its metadata information uniquely.
This eliminates the per object lock required for each to merge.
The metadata is read back and merged by "CompleteMultipartUpload"
without locks when constructing final object.
Co-authored-by: Harshavardhana <harsha@minio.io>
fix: change timedvalue to return previous cached value
caller can interpret the underlying error and decide
accordingly, places where we do not interpret the
errors upon timedValue.Get() - we should simply use
the previously cached value instead of returning "empty".
Bonus: remove some unused code
We need to make sure if we cannot read bucket metadata
for some reason, and bucket metadata is not missing and
returning corrupted information we should panic such
handlers to disallow I/O to protect the overall state
on the system.
In-case of such corruption we have a mechanism now
to force recreate the metadata on the bucket, using
`x-minio-force-create` header with `PUT /bucket` API
call.
Additionally fix the versioning config updated state
to be set properly for the site replication healing
to trigger correctly.
The test expects from DeleteFile to return errDiskNotFound when the disk
is not available. It calls os.RemoveAll() to remove one disk after XL storage
initialization. However, this latter contains some goroutines which can
race with os.RemoveAll() and then the test fails sporadically with
returning random errors.
The commit will tweak the initialization routine of the XL storage to
only run deletion of temporary and metacache data in the background,
so TestXLStorageDeleteFile won't fail anymore.
heal bucket metadata and IAM entries for
sites participating in site replication from
the site with the most updated entry.
Co-authored-by: Harshavardhana <harsha@minio.io>
Co-authored-by: Aditya Manthramurthy <aditya@minio.io>
This PR fixes two issues
- The first fix is a regression from #14555, the fix itself in #14555
is correct but the interpretation of that information by the
object layer code for "replication" was not correct. This PR
tries to fix this situation by making sure the "Delete" replication
works as expected when "VersionPurgeStatus" is already set.
Without this fix, there is a DELETE marker created incorrectly on
the source where the "DELETE" was triggered.
- The second fix is perhaps an older problem started since we inlined-data
on the disk for small objects, CopyObject() incorrectly inline's
a non-inlined data. This is due to the fact that we have code where
we read the `part.1` under certain conditions where the size of the
`part.1` is less than the specific "threshold".
This eventually causes problems when we are "deleting" the data that
is only inlined, which means dataDir is ignored leaving such
dataDir on the disk, that looks like an inconsistent content on
the namespace.
fixes#14767
```
tmp = buf[want:]
```
Would potentially crash when `buf` is truncated for some reason
and does not have the expected bytes, this is of course considered
not normal and is an odd situation. But we do not need to crash
here instead allow for errors to be returned and let callers handle
the errors.
This PR simply adds a warning message when it detects older kernel
versions and warn's them about potential performance issues on this
kernel.
The issue can be seen only with parallel I/O across all drives
on denser setups such as 90 drives or 45 drives per server configurations.
The main goal of this PR is to solve the situation where disks stop
responding to operations. This generally causes an FD build-up and
eventually will crash the server.
This adds detection of hung disks, where calls on disk get stuck.
We add functionality to `xlStorageDiskIDCheck` where it keeps
track of the number of concurrent requests on a given disk.
A total number of 100 operations are allowed. If this limit is reached
we will block (but not reject) new requests, but we will monitor the
state of the disk.
If no requests have been completed or updated within a 15-second
window, we mark the disk as offline. Requests that are blocked will be
unblocked and return an error as "faulty disk".
New requests will be rejected until the disk is marked OK again.
Once a disk has been marked faulty, a check will run every 5 seconds that
will attempt to write and read back a file. As long as this fails the disk will
remain faulty.
To prevent lots of long-running requests to mark the disk faulty we
implement a callback feature that allows updating the status as parts
of these operations are running.
We add a reader and writer wrapper that will update the status of each
successful read/write operation. This should allow fine enough granularity
that a slow, but still operational disk will not reach 15 seconds where
50 operations have not progressed.
Note that errors themselves are not enough to mark a disk faulty.
A nil (or io.EOF) error will mark a disk as "good".
* Make concurrent disk setting configurable via `_MINIO_DISK_MAX_CONCURRENT`.
* de-couple IsOnline() from disk health tracker
The purpose of IsOnline() is to ensure that we
reconnect the drive only when the "drive" was
- disconnected from network we need to validate
if the drive is "correct" and is the same drive
which belongs to this server.
- drive was replaced we have to format it - we
support hot swapping of the drives.
IsOnline() is not meant for taking the drive offline
when it is hung, it is not useful we can let the
drive be online instead "return" errors for relevant
calls.
* return errFaultyDisk for DiskInfo() call
Co-authored-by: Harshavardhana <harsha@minio.io>
Possible future Improvements:
* Unify the REST server and local xlStorageDiskIDCheck. This would also improve stats significantly.
* Allow reads/writes to be aborted by the context.
* Add usage stats, concurrent count, blocked operations, etc.
This is a side-affect of the optimization done in PR #13544 which
causes a certain type of delete operations on given object versions
can cause lastVersion indication to be skipped, which leads to
an `xl.meta` where Versions[] slice is empty while the entire
file is intact by itself.
This PR tries to ensure that such files are visible and deletable
by regular means of listing as null 'delete-marker' and also
avoid the situation where this potential issue might arise.
- speedtest logs calls that were canceled
spuriously, in situations where it should
be ignored.
- all errors of interest are always sent back
to the client there is no need to log them
on the server console.
- PUT failures should negate the increments
such that GET is not attempted on unsuccessful
calls.
- do not attempt MRF on speedtest objects.
In the testing mode, reformatting disks will fail because the healing
code will complain if one disk is in root mode. This commit will
automatically set all disks as non-root if MINIO_CI_CD is set.
The current code considers a pool with all root disks to be as part
of a testing environment even if there are other pools with mounted
disks. This will result to illegitimate writing in root disks.
Fix this by simplifing the logic: require MINIO_CI_CD in order to skip
root disk check.
startup speed-up, currently getFormatErasureInQuorum()
would spend up to 2-3secs when there are 3000+ drives
for example in a setup, simplify this implementation
to use drive counts.
This PR removes an unnecessary state that gets
passed around for DiskIDs, which is not necessary
since each disk exactly knows which pool and which
set it belongs to on a running system.
Currently cached DiskId's won't work properly
because it always ends up skipping offline disks
and never runs healing when disks are offline, as
it expects all the cached diskIDs to be present
always. This also sort of made things in-flexible
in terms perhaps a new diskID for `format.json`.
(however this is not a big issue)
This is an unnecessary requirement that healing
via scanner needs all drives to be online, instead
healing should trigger even when partial nodes
and drives are available this ensures that we
keep the SLA in-tact on the objects when disks
are offline for a prolonged period of time.
- create internal erasure volumes only if the disk is unformatted
- return a copy of format data in xlStorage.ReadAll
- parse env vars only once, to be re-used by xl-storage
This speed-up is intended for faster startup times
for almost all MinIO operations. Changes here are
- Drives are not re-read for 'format.json' on a regular
basis once read during init is remembered and refreshed
at 5 second intervals.
- Do not do O_DIRECT tests on drives with existing 'format.json'
only fresh setups need this check.
- Parallelize initializing erasureSets for multiple sets.
- Avoid re-reading format.json when migrating 'format.json'
from really old V1->V2->V3
- Keep a copy of local drives for any given server in memory
for a quick lookup.
repeated reads on single large objects in HPC like
workloads, need the following option to disable
O_DIRECT for a more effective usage of the kernel
page-cache.
However this optional should be used in very specific
situations only, and shouldn't be enabled on all
servers.
NVMe servers benefit always from keeping O_DIRECT on.
