AIStoreExtended actions (xactions) are batch operations, or jobs, that run asynchronously, report statistics (viewable at runtime and later), can be waited upon, and can be stopped (aborted).
The list of supported jobs can be viewed via the CLI show command and currently includes:
Terminology-wise, in the code we mostly call it xaction by the name of the corresponding software abstraction. But elsewhere, it is simply a job - the two terms are interchangeable.
In the source code, all supported xactions are enumerated here.
For users, there’s an API to start, stop, and wait for a job:
In CLI, there’s ais job command and its subcommands (<TAB-TAB> completions):
Note that
ais startis an alias for theais job startcommand - both (versions) can be used interchangeably.
Not all supported jobs are startable.
Not all supported jobs can be started via ais start or by the corresponding Go or Python API call. Example, the job to copy or (ETL) transform datasets has its own dedicated API (both Python and Go) and CLI.
See e.g.,
ais cp --help
Complete and most recently updated list of supported jobs can be found in this table of job descriptors.
Last (but not the least) is - time. Job execution may take many seconds, sometimes minutes or hours.
Examples include erasure coding or n-way mirroring a dataset, resharding and reshuffling a dataset and more.
Global rebalance gets automatically triggered by any membership changes (nodes joining, leaving, powercycling, etc.) that can be further visualized via ais show rebalance CLI.
Another example would be primary election. AIS proxies provide access points (“endpoints”) for the frontend API. At any point in time there is a single primary proxy that also controls versioning and distribution of the current cluster map. When and if the primary fails, another proxy is majority-elected to perform the (primary) role.
This (election by simple majority) is also a job that cannot be started via ais start or the corresponding API. Similar to global rebalance, it is event-driven. Similar to rebalance, there’s a separate dedicated API to run it administratively.
Rebalance and a few other AIS jobs have their own CLI extensions. Generally, though, you can always monitor xactions via
ais show job xactioncommand that also supports verbose mode and other options.
AIS subsystems integrate subsystem-specific stats - e.g.:
Related CLI documentation:
ais show jobAIStore provides APIs to operate on batches of objects:
For CLI documentation and examples, please see Operations on Lists and Ranges (and entire buckets).
There are two distinct ways to specify the objects: list them (ie., the names) explicitly, or specify a template.
Supported template syntax includes 3 standalone variations - 3 alternative formats:
prefix-{0..100}-suffixprefix-{00001..00010..2}-gap-{001..100..2}-suffixprefix-@100-suffixprefix-@00001-gap-@100-suffixprefix-%06d-suffixIn all cases, prefix and/or suffix are optional.
List APIs take a JSON array of object names, and initiate the operation on those objects.
All the following examples assume that the action is delete and the bucket name is bck, so only the value part of the request is shown:
"value": {"list": "["obj1","dir/obj2"]"} - deletes objects obj1 and dir/obj2 from the bucket bck
"value": {"template": "obj-{07..10}"} - removes the following objects from bck(note leading zeroes in object names):
"value": {"template": "dir-{0..1}/obj-{07..08}"} - template can contain more than one range, this example removes the following objects from bck(note leading zeroes in object names):
"value": {"template": "dir-10/"} - the template defines no ranges, so the request deletes all objects which names start with dir-10/