hadoop-yarn-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Sidharta Seethana (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (YARN-3443) Create a 'ResourceHandler' subsystem to ease addition of support for new resource types on the NM
Date Mon, 13 Apr 2015 19:59:15 GMT

    [ https://issues.apache.org/jira/browse/YARN-3443?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14492978#comment-14492978

Sidharta Seethana commented on YARN-3443:

The javadoc warnings are unrelated to this patch - I don't find any mention of the classes
included in the patch.

> Create a 'ResourceHandler' subsystem to ease addition of support for new resource types
on the NM
> -------------------------------------------------------------------------------------------------
>                 Key: YARN-3443
>                 URL: https://issues.apache.org/jira/browse/YARN-3443
>             Project: Hadoop YARN
>          Issue Type: Sub-task
>          Components: nodemanager
>            Reporter: Sidharta Seethana
>            Assignee: Sidharta Seethana
>         Attachments: YARN-3443.001.patch, YARN-3443.002.patch, YARN-3443.003.patch, YARN-3443.004.patch,
> Today, support for CPU and memory as resources (on linux) are implemented in a way that
cannot be easily extended to other new resource types (e.g network/disk). For example, some
functionality cgroups functionality is implemented in LCE (mountCgroups) and the rest in CgroupsLCEResourcesHandler.
CPU specific functionality is also implemented in CgroupsLCEResourcesHandler - using this
handler automatically enables CPU as a resource.  Some cgroups functionality requires elevated/super-user
privileges and needs to be implemented via the container-executor binary. Implementing support
for a new resource type in linux using the existing classes/mechanisms would be messy (for
example, we might have to significantly modify/bloat CgroupsLCEResourceHandler).  As an alternative,
we have implemented a new ‘ResourceHandler’ mechanism that makes things cleaner and enables
easier addition of new resource types.  When adding support for a new resource type in the
NM (from an isolation/enforcement perspective), there are three different pieces required
> 1) generic cgroups utilities that can be re-used across multiple resource handler ( e.g
for CPU, Network, Disk). For example for net_cls we want to be able to create new cgroups,
update cgroup params, read cgroup params etc. 
> 2) A mechanism to execute ‘PrivilegedOperation’s whose functionality requires super-user
privileges and is implemented by container-executor binary
> 3) Implementation that is specific to a resource type ( i.e network, disk would each
have an implementation that provides isolation/enforcement for that resource type)
> Corresponding to the three pieces listed above, the patch for YARN-3443 provides the
following :
> 1) cgroups functionality that can be used across different resource types.  CGroupsHandler.java
specifies the interface and implementation is in CGroupsHandlerImpl.java . New cgroups controller
types can be easily added to CGroupsHandler.java as and when necessary
> 2) PrivilegedOperation.java and PrivilegedOperationExecutor.java wrap the container-executor
binary and provide a way of executing operations that require elevated privileges. There are
also utility functions that help ‘batching’ of certain kinds of operations in order to
avoid multiple invocations of the container-executor binary
> 3) ResourceHandler.java specifies an interface that custom resource handlers are expected
to implement. This interface provides hooks for various operations during a container lifecyle
- bootstrap, preStart, postComplete, reAcquire, teardown.  Each of these hooks return a list
of privileged operations - this is done so that the resulting set of privileged operations
can be batched for performance reasons, if necessary. ResourceHandlerChain.java provides a
simple chaining mechanism across multiple resource handlers. This is useful when multiple
resource handlers are in place. They can be chained in sequence - e.g cpu, network, disk .
A resource handler chain would hook in directly into LCE at various points in the container
life cycle. 

This message was sent by Atlassian JIRA

View raw message