Windows NT Server Configuration and Tuning for Optimal SAS Server Performance

Transcription

1 Windows NT Server Configuration and Tuning for Optimal SAS Server Performance Susan E. Davis Compaq Computer Corp. Carl E. Ralston Compaq Computer Corp.

2 Our Role Onsite at SAS Corporate Technology Center in Cary, NC Characterize Performance of SAS on Compaq Hardware Size and Configure New Systems For Customers Diagnose and Recommend Solutions For Performance Problems

3 Topics Planning Your System CPUs Memory Virtual & Physical I/O Hardware Disks, Controllers & PCI Configuring I/O SAS Options

4 Planning Your System Plan Detailed Configuration Early Initial Configuration Based On Assumptions Ongoing Analysis Required To Validate System and Application Tuning Can Help, But Performance Always Limited By Underlying Hardware

5 CPUs SAS v8.x Single Threaded Multiple SAS Jobs Needed To Use Multiple CPUs Want Highest Processor Speed

6 Memory Virtual Address Virtual Address Space vs. Physical RAM Up to 2GB Process Private Space Per Job When Sum of All Process Virtual Address Spaces Greater Than Physical RAM Paging Occurs Estimate Address Space Needs Amount Per Job * Nbr. Of Jobs

7 Memory Physical RAM Memory In Servers Arranged Into Banks All slots in a bank must be filled at same time with same size DIMM No Effective Use Beyond 4GB Plan Purchases To Preserve Investment

8 Memory - Physical Initially Need 1GB of RAM Server Comes With 128MB Included Has 4 memory slots (and 4 banks) 128MB 128MB 256MB 512MB 128MB 512MB 512MB 128MB 1024MB What Happens When You Need To Upgrade to 2GB? 3GB?

9 I/O Hardware For SAS Performance I/O Throughput Is Important Measure (MB/s) Disk Controller PCI Bus RPM SCSI Fibre Width Speed

10 I/O Hardware - Disks Need 72GB of Disk Space x 36.4GB 40 MB/s 4 x 18.2GB x 9.1GB 256

11 I/O Hardware - Controllers Need to Configure 250GB of Disk Connect 14 x 18.2GB 15K RPM Disks Fibre 100 MB/s Ultra x Ultra 3 320

12 I/O Hardware - PCI Want To Configure 1 TB of Storage 56 x 18.2 GB 15K RPM Disks 4 Dual Channel Storage Shelves 4 Dual Channel Smart Array Controllers

13 I/O Hardware - PCI Each Controller Goes in a PCI Slot Multiple PCI Slots and Buses In Each Server Server Specific Configurations Type 32-bit/33MHz 64-bit/33MHz 64-bit/66MHz MB/s

14 I/O Hardware PCI ProLiant CPU Server Spread Load Over Multiple Channels 64-bit 33MHz 64-bit 33MHz 64-bit 66MHz * * 9 10 * 11 *

15 Configuring I/O How are you going to use this storage? Operating System Pagefile SAS Software SAS Work SAS User SAS Data

16 Definitions Configuring I/O Bind Physical Disks into a Volume (array) Volumes Can be divided into logical drives / Partitions Avoid Multiple Partitions On A Single Volume Assigned Drive Letters Via Disk Admin

17 Configuring I/O Individual Volumes For Operating System SAS Software Mirror (RAID-1) For Availability Pagefile Separate (1.5 2 times RAM) Change Pagefile to Fixed Size

18 Configuring I/O SAS Work Has Lots of I/O Use Disk Striping (RAID-0) To Distribute Do NOT Use RAID-5 Writes are slow in RAID-5 Sizing Nbr. Of Jobs * Space Per Job Sort Requires > 3 x Data Set Size

19 Configuring I/O SAS User Programs, Log Files SAS Data Permanent SAS Data Good Candidates For RAID-5

20 Configuring I/O RAID Hardware Vs Software Stripe Width = 64KB / Nbr. Of Members Spread Disks Over Multiple SCSI Buses Other Considerations Disk Effectively Full At 70% - 80% Disk Defragmentation Utility

21 SAS Options FULLSTIMER Memory Size Sort Size Buffer Size / Utility Buffer Size Nbr. Of Buffers / Nbr. Of Utility Buffers Scatter Gather I/O

22 SAS Options FULLSTIMER Use To Monitor Effect Of Changes MEMSIZE Virtual Address Space For SAS Change Windows Default (0) Physical RAM / Nbr. Of Jobs SORTSIZE Virtual Address Space For Sort Change Windows Default (2m) MEMSIZE 16M

23 SAS Options BUFSIZE / UBUFSIZE Size Of I/O Buffers N * Stripe Width * Nbr. Of Members BUFNO / UBUFNO Number Of I/O Buffers SGIO Bypass NT File Cache

24 Conclusions Plan System In Advance I/O Tuning Critical For SAS Tuning Ongoing Defragment Disks Test Effect Of SAS Options

25 About the Author Carl E. Ralston Phone: (919) Senior Member Corporate Technical Staff Web: