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
* Update the GetConfig admin API to use the latest version of
configuration, along with fixes to the corresponding RPCs.
* Remove mutex inside the configuration struct, and inside
notification struct.
* Use global config mutex where needed.
* Add `serverConfig.ConfigDiff()` that provides a more granular diff
of what is different between two configurations.
This fix removes logrus package dependency and refactors the console
logging as the only logging mechanism by removing file logging support.
It rearranges the log message format and adds stack trace information
whenever trace information is not available in the error structure.
It also adds `--json` flag support for server logging.
When minio server is started with `--json` flag, all log messages are
displayed in json format, with no start-up and informational log
messages.
Fixes#5265#5220#5197
This adds configurable data and parity options on a per object
basis. To use variable parity
- Users can set environment variables to cofigure variable
parity
- Then add header x-amz-storage-class to putobject requests
with relevant storage class values
Fixes#4997
This change introduces following simplified steps to follow
during config migration.
```
// Steps to move from version N to version N+1
// 1. Add new struct serverConfigVN+1 in config-versions.go
// 2. Set configCurrentVersion to "N+1"
// 3. Set serverConfigCurrent to serverConfigVN+1
// 4. Add new migration function (ex. func migrateVNToVN+1()) in config-migrate.go
// 5. Call migrateVNToVN+1() from migrateConfig() in config-migrate.go
// 6. Make changes in config-current_test.go for any test change
```
