orca.cod.control
Class XenControl

java.lang.Object
  orca.cod.control.XenControl

All Implemented Interfaces:

IResourceControl, IInitialize, IRecover, ISerialize

Direct Known Subclasses:

XenResizeControl

public class XenControl
extends java.lang.Object
implements IResourceControl

XenControl handles virtual machine reservations (e.g., Xen) for an authority-side mapper (CodMapper). VMs are hosted on inventory nodes running VMMs. Each VM occupies a "sliver" of the hosting node. The key issues are (1) how to bin-pack VMs onto VMMs, and (2) how to assign resources to each sliver. These problems are particularly difficult if reservations "flex" in a way that changes the size of the slivers. The job here is basically to create and release virtual Node objects to represent the virtual machines. Configuration properties (e.g., names and addresses) are assigned on transferIn() of the node to an AuthoritySlice, and the VM is instantiated in the subsequent RAL call from NodeGroup. Currently the allocation policy has the following limitations: - Any flex in a reservation results in a change in the number of VMs, rather than a sliver flex. To flex VM slivers, we need better tracking of slivers, and a way to short-circuit priming of any resources added to the VMs, i.e., AuthorityReservation must distinguish growing VMs from growing the number of VMs in a reservation. - The resources assigned to a VM/sliver are in units of "computons". Computons are simple because they define a fixed "resource ratio" of hardware resources (e.g., CPU:memory:disk following Amdahl's rule). We have no way to allocate slivers with different resource ratios from the same host. The idea of supporting a discrete set of computon types with different ratios has been called "molecules" or "compounds". The current scheme can handle multiple compounds, but it (in essence) statically partitions compound types across the VMM inventory. - VMMs are divided into "pools" indexed by type. Thus each pool must have a different type. All hosting servers (VMMs) in a pool are viewed as equivalent and interchangeable. - Each pool/type has a configured computonsPerNode. Different pools/types may have different computonsPerNode, even if the physical servers in the pools are equivalent. - If type T is a VMM type, then a request for one unit of type T is filled with one VM bound to one computon on a VMM node of type T. For example, a given class of server might be split into multiple pools for small, medium, and large VMs: pools with fewer computonsPerNode host larger VMs. Note also that the resource ratio of each VM is the same as its hosting server, thus we can divide different server classes with different resource ratios (e.g., big memory vs. small memory) into different pools; VMs allocated from the big-memory pool have more memory than those allocated from the small-memory pool.

Field Summary

protected IActor	actor
protected ID	guid
protected LoggingTool	logger
protected java.util.HashMap<ResourceType,ResourceSet>	nodePools
protected java.util.HashMap<ResourceType,BinPool>	pools Hosting candidates (VMMs) for each VM type are indexed by their free capacity in BinPools, one pool for each type.
static java.lang.String	PropertyGuid
static java.lang.String	PropertyResourceTypePrefix
static java.lang.String	PropertyResourceTypesCount
static java.lang.String	ResourceComputonsPrefix

Constructor Summary

XenControl()

Method Summary

ResourceSet	assign(AuthorityReservation r) Allocates virtual machines to fill a request that has been approved by the mapper.
protected ResourceSet	assign(AuthorityReservation r, ResourceType type, int needed)
void	available(ResourceSet rset)
void	configSlivers(ResourceType type, int computonsPerNode) Indicate that VMM nodes of a particular type are to be broken into a specified number of computons per node.
void	configure(java.util.Properties p)
ResourceSet	correctDeficit(AuthorityReservation r)
ResourceSet	correctFailed(ResourceSet rset)
void	donate(ResourceSet rset) Registers server-side VMM inventory.
void	eject(ResourceSet rset)
void	freed(ResourceSet rset)
ID	getGuid()
ResourceType[]	getTypes()
protected NodeGroup	groupFromSet(ResourceSet rset) Returns the NodeGroup underlying a given resource set.
void	initialize() Initializes the object.
protected void	instantiateVMs(NodeGroup group, BinPool pool, int needed, int computons, ResourceType type) Fills a NodeGroup with virtual Node objects to fill a virtual reservation request, allocated from selected host nodes in the specified VMM pool.
protected void	internalError(java.lang.String string)
protected void	logError(java.lang.String string)
void	logException(java.lang.String err, java.lang.Exception e)
protected BinPool	poolForRequest(ResourceType type) Returns the BinPool with allocation state for VMM inventory of the type matching the passed resource set.
void	release(ResourceSet rset) Releases VM resources back to their inventory pool.
protected void	releaseToVMMs(NodeGroup group, BinPool pool) Releases the computons held by virtual nodes in a NodeGroup back to their hosting VMMs, and detaches the nodes from the NodeGroup.
void	reset(java.util.Properties p) De-serializes the object from the given properties list.
protected void	resetSlivers(java.util.Properties p)
protected void	revisit(BinPool pool, NodeGroup inventory, NodeGroup incoming) Reallocates the computons held by virtual nodes in a NodeGroup from their hosting VMMs.
void	revisit(IActor actor, java.util.Properties p) Recovers state of the component using a previously saved properties list and a references to the actor this component belongs to.
void	revisit(ResourceReservation r) Reallocate VM resources from their inventory pool.
java.util.Properties	save() Serializes the object into a properties list.
void	save(java.util.Properties p) Serializes the object into the given properties list.
protected void	saveSlivers(java.util.Properties p)
protected Node	selectAndGetFromVMM(BinPool pool, int computons) Selects a VMM to host a new virtual machine, and allocates the requested number of computons from it.
void	setActor(IActor actor)
protected IConcreteSet	shrink(AuthorityReservation r, int toRemove)
int	unavailable(ResourceSet rset)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

PropertyResourceTypesCount

public static final java.lang.String PropertyResourceTypesCount

See Also:

Constant Field Values

PropertyResourceTypePrefix

public static final java.lang.String PropertyResourceTypePrefix

See Also:

Constant Field Values

ResourceComputonsPrefix

public static final java.lang.String ResourceComputonsPrefix

See Also:

Constant Field Values

PropertyGuid

public static final java.lang.String PropertyGuid

See Also:

Constant Field Values

guid

protected ID guid

logger

protected LoggingTool logger

pools

protected java.util.HashMap<ResourceType,BinPool> pools

Hosting candidates (VMMs) for each VM type are indexed by their free capacity in BinPools, one pool for each type.

nodePools

protected java.util.HashMap<ResourceType,ResourceSet> nodePools

actor

protected IActor actor

Constructor Detail

XenControl

public XenControl()

Method Detail

setActor

public void setActor(IActor actor)

Specified by:

setActor in interface IResourceControl

initialize

public void initialize()
                throws java.lang.Exception

Description copied from interface: IInitialize

Initializes the object.

Specified by:

initialize in interface IInitialize

Throws:

java.lang.Exception

configSlivers

public void configSlivers(ResourceType type,
                          int computonsPerNode)

Indicate that VMM nodes of a particular type are to be broken into a specified number of computons per node. Mandatory preconfiguration: exactly once per VMM type.

Parameters:

type - node type

computonsPerNode - how many computons per node

eject

public void eject(ResourceSet rset)
           throws java.lang.Exception

Specified by:

eject in interface IResourceControl

Throws:

java.lang.Exception

available

public void available(ResourceSet rset)
               throws java.lang.Exception

Specified by:

available in interface IResourceControl

Throws:

java.lang.Exception

unavailable

public int unavailable(ResourceSet rset)
                throws java.lang.Exception

Specified by:

unavailable in interface IResourceControl

Throws:

java.lang.Exception

donate

public void donate(ResourceSet rset)
            throws java.lang.Exception

Registers server-side VMM inventory. Note: modifies the passed resource set to reflect number of computons per node.

Specified by:

donate in interface IResourceControl

Parameters:

rset - the resources being donated

Throws:

java.lang.Exception

correctDeficit

public ResourceSet correctDeficit(AuthorityReservation r)
                           throws java.lang.Exception

Specified by:

correctDeficit in interface IResourceControl

Throws:

java.lang.Exception

assign

public ResourceSet assign(AuthorityReservation r)
                   throws java.lang.Exception

Allocates virtual machines to fill a request that has been approved by the mapper.

Specified by:

assign in interface IResourceControl

Parameters:

iset - inventory set to fill request from

needed - number of units needed to fill request

Returns:

a resource set to fill the request (may be partial or empty)

Throws:

java.lang.Exception - with no side effects if error

assign

protected ResourceSet assign(AuthorityReservation r,
                             ResourceType type,
                             int needed)
                      throws java.lang.Exception

Throws:

java.lang.Exception

shrink

protected IConcreteSet shrink(AuthorityReservation r,
                              int toRemove)
                       throws java.lang.Exception

Throws:

java.lang.Exception

freed

public void freed(ResourceSet rset)
           throws java.lang.Exception

Specified by:

freed in interface IResourceControl

Throws:

java.lang.Exception

release

public void release(ResourceSet rset)
             throws java.lang.Exception

Releases VM resources back to their inventory pool. Note: this implementation does not support releasing nodes that represent modifications to existing nodes. Override this method if your control resizes/modifies nodes in a reservation.

Specified by:

release in interface IResourceControl

Parameters:

rset - the resource set being released

Throws:

java.lang.Exception

revisit

public void revisit(ResourceReservation r)
             throws java.lang.Exception

Reallocate VM resources from their inventory pool. Used on reset/recovery.

Specified by:

revisit in interface IResourceControl

Parameters:

rset - the resource set being reallocated

Throws:

java.lang.Exception

instantiateVMs

protected void instantiateVMs(NodeGroup group,
                              BinPool pool,
                              int needed,
                              int computons,
                              ResourceType type)
                       throws java.lang.Exception

Fills a NodeGroup with virtual Node objects to fill a virtual reservation request, allocated from selected host nodes in the specified VMM pool. Throw an exception if the result cannot be fully met: in this case, the partial set is returned, and must be released if it is not to be used.

Parameters:

group - empty NodeGroup to fill with virtual nodes

pool - inventory pool of VMM candidates to allocate from

needed - number of VMs needed

computons - the number of computons per VM

Throws:

java.lang.Exception - if allocation is incomplete

releaseToVMMs

protected void releaseToVMMs(NodeGroup group,
                             BinPool pool)

Releases the computons held by virtual nodes in a NodeGroup back to their hosting VMMs, and detaches the nodes from the NodeGroup.

revisit

protected void revisit(BinPool pool,
                       NodeGroup inventory,
                       NodeGroup incoming)

Reallocates the computons held by virtual nodes in a NodeGroup from their hosting VMMs. Used on reset/recovery.

selectAndGetFromVMM

protected Node selectAndGetFromVMM(BinPool pool,
                                   int computons)
                            throws java.lang.Exception

Selects a VMM to host a new virtual machine, and allocates the requested number of computons from it.

Parameters:

pool - inventory pool of candidate VMMs

computons - number of computons to allocate

Returns:

a virtual node hosted on selected VMM host

Throws:

java.lang.Exception - if no eligible candidates

groupFromSet

protected NodeGroup groupFromSet(ResourceSet rset)
                          throws java.lang.Exception

Returns the NodeGroup underlying a given resource set. The ResourceSet could be a free pool or a resource set for and extend or release. Identical to CodMapper.groupFromSet.

Parameters:

rset - resource set of some type

Returns:

concrete set underlying this resource set

Throws:

java.lang.Exception - if no concrete set, or if not a NodeGroup

poolForRequest

protected BinPool poolForRequest(ResourceType type)
                          throws java.lang.Exception

Returns the BinPool with allocation state for VMM inventory of the type matching the passed resource set.

Parameters:

rset - resource set of some type

Returns:

inventory pool for VMM hosting nodes matching the type

Throws:

java.lang.Exception - if no inventory pool

internalError

protected void internalError(java.lang.String string)
                      throws java.lang.Exception

Throws:

java.lang.Exception

logError

protected void logError(java.lang.String string)

logException

public void logException(java.lang.String err,
                         java.lang.Exception e)

saveSlivers

protected void saveSlivers(java.util.Properties p)
                    throws java.lang.Exception

Throws:

java.lang.Exception

resetSlivers

protected void resetSlivers(java.util.Properties p)
                     throws java.lang.Exception

Throws:

java.lang.Exception

save

public java.util.Properties save()
                          throws java.lang.Exception

Description copied from interface: ISerialize

Serializes the object into a properties list.

Specified by:

save in interface ISerialize

Returns:

properties list representing this object

Throws:

java.lang.Exception

save

public void save(java.util.Properties p)
          throws java.lang.Exception

Description copied from interface: ISerialize

Serializes the object into the given properties list.

Specified by:

save in interface ISerialize

Parameters:

p - properties list to serialize the object into

Throws:

java.lang.Exception

reset

public void reset(java.util.Properties p)
           throws java.lang.Exception

Description copied from interface: ISerialize

De-serializes the object from the given properties list.

Specified by:

reset in interface ISerialize

Parameters:

p - properties list containing the serialized version of the object

Throws:

java.lang.Exception

revisit

public void revisit(IActor actor,
                    java.util.Properties p)
             throws java.lang.Exception

Description copied from interface: IRecover

Recovers state of the component using a previously saved properties list and a references to the actor this component belongs to. The component can use the actor object to access other objects necessary for its complete recovery.

Specified by:

revisit in interface IRecover

Parameters:

actor - actor object the component belongs to

p - properties list containing configuration data about the component

Throws:

java.lang.Exception

getTypes

public ResourceType[] getTypes()

Specified by:

getTypes in interface IResourceControl

configure

public void configure(java.util.Properties p)
               throws java.lang.Exception

Throws:

java.lang.Exception

correctFailed

public ResourceSet correctFailed(ResourceSet rset)
                          throws java.lang.Exception

Specified by:

correctFailed in interface IResourceControl

Throws:

java.lang.Exception

getGuid

public ID getGuid()

Specified by:

getGuid in interface IResourceControl