Currently, cache purges are triggered as soon as the low watermark is exceeded.
To reduce IO this should only be done when reaching the high watermark.
This simplifies checks and reduces all calls for a GC to go through
`dcache.diskSpaceAvailable(size)`. While a comment claims that
`dcache.triggerGC <- struct{}{}` was non-blocking I don't see how
that was possible. Instead, we add a 1 size to the queue channel
and use channel semantics to avoid blocking when a GC has
already been requested.
`bytesToClear` now takes the high watermark into account to it will
not request any bytes to be cleared until that is reached.
To allow better control the cache eviction process.
Introduce MINIO_CACHE_WATERMARK_LOW and
MINIO_CACHE_WATERMARK_HIGH env. variables to specify
when to stop/start cache eviction process.
Deprecate MINIO_CACHE_EXPIRY environment variable. Cache
gc sweeps at 30 minute intervals whenever high watermark is
reached to clear least recently accessed entries in the cache
until sufficient space is cleared to reach the low watermark.
Garbage collection uses an adaptive file scoring approach based
on last access time, with greater weights assigned to larger
objects and those with more hits to find the candidates for eviction.
Thanks to @klauspost for this file scoring algorithm
Co-authored-by: Klaus Post <klauspost@minio.io>
- adding oauth support to MinIO browser (#8400) by @kanagaraj
- supports multi-line get/set/del for all config fields
- add support for comments, allow toggle
- add extensive validation of config before saving
- support MinIO browser to support proper claims, using STS tokens
- env support for all config parameters, legacy envs are also
supported with all documentation now pointing to latest ENVs
- preserve accessKey/secretKey from FS mode setups
- add history support implements three APIs
- ClearHistory
- RestoreHistory
- ListHistory
- add help command support for each config parameters
- all the bug fixes after migration to KV, and other bug
fixes encountered during testing.
This PR changes cache on PUT behavior to background fill the cache
after PutObject completes. This will avoid concurrency issues as in #8219.
Added cleanup of partially filled cache to prevent cache corruption
- Fixes#8208
- with recent commit 1fb2e9ef95, config
can no longer be updated by editing config.json. This is because config
has been migrated inside the minio backend. Update documentation on
how to set/get configuration using mc admin config command.
This PR adds disk based edge caching support for minio server.
Cache settings can be configured in config.json to take list of disk drives,
cache expiry in days and file patterns to exclude from cache or via environment
variables MINIO_CACHE_DRIVES, MINIO_CACHE_EXCLUDE and MINIO_CACHE_EXPIRY
Design assumes that Atime support is enabled and the list of cache drives is
fixed.
- Objects are cached on both GET and PUT/POST operations.
- Expiry is used as hint to evict older entries from cache, or if 80% of cache
capacity is filled.
- When object storage backend is down, GET, LIST and HEAD operations fetch
object seamlessly from cache.
Current Limitations
- Bucket policies are not cached, so anonymous operations are not supported in
offline mode.
- Objects are distributed using deterministic hashing among list of cache
drives specified.If one or more drives go offline, or cache drive
configuration is altered - performance could degrade to linear lookup.
Fixes#4026
