GRAM: Software Provider Forum Stuart Martin Computational Institute, University of Chicago & Argonne National Lab TeraGrid 2007 Madison, WI

2 GRAM - Basic Job Submission and Control Service l A uniform service interface for remote job submission and control –Includes file staging and I/O management –Includes reliability features –Supports basic Grid security mechanisms –Asynchronous monitoring –Interfaces with local resource managers, simplifies the job of metaschedulers/brokers l GRAM is not a scheduler. –No scheduling –No metascheduling/brokering

3 GRAM Versions in GT4 l GRAM2 (Pre-WS GRAM) –Proprietary Protocol based implementation –Gatekeeper and Job Manager l GRAM4 (WS GRAM) –Web Services-based implementation –Managed Job Factory Service (MJFS) –Managed Executable Job Service (MEJS)

4 Performance Comparisons

5 Concurrent Jobs (as in paper) Stage In Stage Out File Clean Up Unique Job Dir GRAM2GRAM4 None No X10KB No X10KB Yes Average seconds per 1000 jobs Condor-g to GRAM to Condor LRM

6 Concurrent Jobs (as will be in GT 4.0.5) Stage In Stage Out File Clean Up Unique Job Dir GRAM2GRAM4 None No X10KB No X10KB Yes Average seconds per 1000 jobs Condor-g to GRAM to Condor LRM

7 Improving performance for staging jobs l Adding local method call mechanism for general use in Java WS Core (4.0.5) –GRAM is doing this with RFT –Any service which calls another in-process service could make similar modifications for local calls and likely benefit from improved performance l Adding caching of the GridFTP server connections in RFT (4.0.6)

8 Sequential Jobs Delegation Stage In Stage Out GRAM2GRAM4 None N/A1.70 Per JobNone Per Job1X10KBNone Shared1X10KBNoneN/A5.41 Per Job1X10KB Shared1X10KB N/A7.91 Average seconds per job (Fork)

9 Sequential Jobs Delegation Stage In Stage Out GRAM2GRAM4 None N/A1.46 Per JobNone Per Job1X10KBNone Shared1X10KBNoneN/A3.51 Per Job1X10KB Shared1X10KB N/A3.67 Average seconds per job (Fork)

10 GRAM Auditing

11 TG Gateways l Lower the barrier for scientists and their applications to use TeraGrid resources l Provide an application or domain-specific interface that a scientist can easily understand l Each gateway may have 100s or 1000s of users accessing TG resources l Must be efficient and scale

12 Use Cases l Group Access –For efficiency, a “community” credential is used to multiplex many users over a single ID l Query Job Accounting –Gateways need a remote interface to obtain the TG units charged for their user’s jobs l Auditing –Grid services provide access to resources –TG Resource Providers need a record of actions performed by services

13 Requirements From Use Cases l Grid Job Identifier l Remote client interface to auditing and accounting information l Creation of service audit and accounting information l Access to remote LRM accounting information from the audit service l Scalability in storing information/records l Secure access (authentication and authorization) to audit and accounting information

14 Grid Job Identifier l Uniquely identifies a job l Shared between the client (Gateway) and service (TG RP) l Obtained in the normal service interaction/protocol l In GRAM4 it’s the EPR converted l In GRAM2 it’s the job contact (as is) l GRAM4 Example >>>

15 GRAM4 EPR: <ns4:ReferenceParameters xmlns:ns4=" Grid Job ID: QDzjbFVYImtVg8

16 Remote Client Interface l Flexible query interface to retrieve audit and accounting records l Define an operation “getChargeForJob” to return the units consumed by a Grid Job ID l Keep audit service interface separate from GRAM service to allow flexible deployment scenarios –Allow a single audit service for multiple GRAM services –Same client interface could be used for other services, for example, charging for data storage or transfers l OGSA-DAI satisfies these requirements

17 Creation of Service Auditing Information l Added GRAM audit record creation upon job termination –Record fields: Job_grid_id, local_job_id, submission_job_id, subject_name, username, creation_time, queued_time, stage_in_gid, stage_out_gid, clean_up_gid, gt_verison, rm_type, job_description, success_flag –Gerson Galang (APAC) contribution for GRAM4 audit record creation at beginning of job, update after LRM submission, and final update upon termination –Records are needed soon after job termination l Accounting information is created by the local resource managers

18 Access to LRM Accounting Information l TeraGrid uploads all LRM accounting information from each TG site to a central DB (TGCDB) l The OGSA-DAI service can be configured to access the remote TGCDB

19 Scalability in Storing Information/Records l Estimated that system should handle 100,000+ records l GRAM service inserts records directly into audit DB l Audit DB must be local to GRAM service to assure reliability l Implemented to use either postgress or MySQL

20 Secure access l Standard authentication and authorization methods should be used to limit access to the audit and accounting information –Clients must present a valid X.509 certificate –Access can be controlled based on a range of policies l Current policy is to allow access iff the DN of the requestor matches the DN in the audit record

21 GT4 Java Container Delegation Resource Manager RFT RM Accounting LEAD Gateway Resource Provider Site TG Central Accounting DB RFT Audit Table GRAM Audit Table AMIE OGSA DAI WS GRAM 1, Compute Cluster

22 Sequence Description 1. Gateway submits job and gets an EPR on the reply 2. Gateway controls and monitors job with EPR 3. GRAM submits and monitors job in RM 4. GRAM inserts audit record at end of job 5. RM writes job accounting record 6. AMIE uploads RM accounting records to TGCDB. The RM accounting record is converted to TG accounting units. 7. Gateway locally converts EPR to GJID 8. Gateway calls OGSA-DAI getChargeForJob with GJID and gets the job usage on the reply 9. OGSA-DAI processes remote join between GRAM audit and TGCDB