By definition, eXtended actions (aka xactions) are batch operations that run asynchronously, are monitorable, can be aborted, and - most importantly - may take many seconds (minutes, sometimes hours) to execute.

Examples include erasure coding or n-way mirroring a dataset, resharding and reshuffling a dataset, and many more.

In the source code, all supported - and the most recently updated - xactions are enumerated here.

All eXtended actions support generic API and CLI to show both common counters (byte and object numbers) as well as operation-specific extended statistics.

Global rebalance that gets triggered by any membership changes (nodes joining, leaving, powercycling, etc.) can be further visualized via ais show rebalance CLI.

Rebalance and a few other AIS jobs have their own CLI extensions. Generally, though, you can always monitor xactions via ais show job xaction command that also supports verbose mode and other options.

AIS subsystems integrate subsystem-specific stats - e.g.:

Related CLI documentation:

Table of Contents

Operations on multiple selected objects

AIStore provides APIs to operate on batches of objects:

API Message (apc.ActionMsg) Description
apc.ActCopyObjects copy multiple objects
apc.ActDeleteObjects delete --/--
apc.ActETLObjects etl (transform) --/--
apc.ActEvictObjects evict --/--
apc.ActPrefetchObjects prefetch --/--
apc.ActArchive archive --/--

For CLI documentation and examples, please see Operations on Lists and Ranges.

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:

  1. bash (or shell) brace expansion:
    • prefix-{0..100}-suffix
    • prefix-{00001..00010..2}-gap-{001..100..2}-suffix
  2. at style:
    • prefix-@100-suffix
    • prefix-@00001-gap-@100-suffix
  3. fmt style:
    • prefix-%06d-suffix

In all cases, prefix and/or suffix are optional.


List APIs take a JSON array of object names, and initiate the operation on those objects.

Parameter Description
objnames JSON array of object names


Parameter Description
template The object name template with optional range parts. If a range is omitted the template is used as an object name prefix


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):

  • obj-07
  • obj-08
  • obj-09
  • obj-10

"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):

  • dir-0/obj-07
  • dir-0/obj-08
  • dir-1/obj-07
  • dir-1/obj-08

"value": {"template": "dir-10/"} - the template defines no ranges, so the request deletes all objects which names start with dir-10/