Performance Measurement Points

1
Performance Measurement Points

• Sockets, plain text and grid services
• Paul Mealor

2
Menu

• First stage PMP
• Grid Services
• Grid Services PMP

3
First stage PMP

• First step
• Simple protocols and implementation
• Cron used as the scheduler
• One single schedule that we overwrite
• Required security add in SSL/Shibboleth/whatever

4
First stage PMP
PMP control interface
crontab
Cron
Server-side component
DB
Database frontend (MySQL? Web service?)
5
First stage PMP - schedules

• 0 /2 iperf c some.server.edu
• Crontab style schedule times
• Tool names to use
• Only authorised tools with wrapper scripts may be
  used
• Parameters to pass
• The wrapper script will do any required checking
• Arbitrary commands cannot be executed

6
Questions

• Get scheduler to specifically control server-side
  tools
• YTL has a framework for asking for a server tool
  to be started
• But maybe the scheduler already thinks about
  server side stuff
• No particularly good way to do inter-PMP schedule
  negotiations

7
A brief introduction to Grid Services

• OGSA (Open Grid Services Architecture)
• OGSI (Open Grid Services Infrastructure)
• An extension of web services
• Mandated functions plus extension to WSDL
• Provides
• Service data
• Notification
• Registry interface
• Instance creation via factories lifetime
  management
• Implementation Globus Toolkit 3
• Framework for creating new services, plus some
  example and implementations of job managers c.

8
A brief introduction to Grid Services

• Imagine one of the OGSA/OGSI piccies here

9
Port types, operations service data

• GridService
• findServiceData, setServiceData,
  requestTerminationBefore, requestTerminationAfter,
  destroy
• interface, serviceDataName, factoryLocator,
  gridServiceHandle, gridServiceReference,
  findServiceDataExtensibility, setServiceDataExtens
  ibility, terminationTime,
• NotificationSource
• subscribe
• notifiableServiceDataName
• NotificationSink
• deliverNotification
• NotificationSubscription
• Service data subscriptionException, sinkLocator

• Factory
• createService
• createServiceExtensibility
• ServiceGroup
• Service data membershipContentRule, entry
• ServiceGroupEntry
• Service data memberServiceLocator, content
• ServiceGroupRegistration
• add, remove
• HandleResolver
• findByHandle

10
A brief introduction to Grid Services

• Globus Toolkit 3
• Java
• Communications via XML (JAX-RPC SOAP)
• Servlets can run in, say, Tomcat or in custom
  test container
• GSI security directly supported
• Plugging in Shibboleth may be tricky

11
OGSA PMP

• Using Globus Toolkit 3
• Which is based on pre-April 5 version of OGSI
• Permanent, persistent PMP interface
• No sense of a non-persistent component to a PMP
  (maybe)
• Can still use Cron as the scheduler
• But backends could talk to anything
• Clients talk about metrics and measurements
• PMP thinks about tools

12
OGSA PMP with Cron backend
Service data
config
Grid service port type
Subscription
WSDL
Implementation
PMP port type
Manipulate schedule
Schedule Writer
Schedule Writer
config
crontab
Cron
Wrapper
Tool
13
OGSA PMP - Discovery
Scheduler
Scheduler
Project-specific query results
Custom registry
Custom port type
Service data query results
Write schedule
Registry port type
Register

• Standard registry interface can be re-used in
  completely different registries, but exactly the
  same PMP

14
An OGSA client

• Stubs and beans can be created from WSDL
• Search for PMPs in a registry
• The registry may not be entirely public
• Call PMP functions via stubs
• SOAP-RPC behind the scenes
• The OGSA client would be a scheduler

15
Problems and Questions

• Tools which require a server and a client
• Original plan was to force OGSA client to match
  up the server and client
• Maybe much better for PMPs to negotiate
• Clever PMPs
• Perform scheduling on the PMPs
• All PMPs negotiate all the time
• Loads of problems
• Can we design the protocols to deal with it
  if/when it comes?

16
Problems and Questions

• Deleting or changing schedules
• Should this be allowed?
• Need good security with it
• Can we make use of the factory system?
• If an OGSA client wants to add part of a
  schedule, maybe that should create a new instance
  of a PMP schedule
• Might simplify schedule updating
• Do we want loads of instances sitting around?

17
Notes from yesterday

• What Ive described is probably more like the PMC
  interface
• But theres no particular reason the PMP itself
  couldnt be a Grid Service
• Registration process neednt be to a
  globally-accessible registry
• But maybe the overheads are unacceptable

18
End