Skip to main content
Start a Conversation

Unsolved

This post is more than 5 years old

odurasler

103 Posts

4438

December 15th, 2009 08:00

Performance Estimate Calculator

All,

Just checking to see if anyone has a calculator (via programs, spreadsheets, etc) before I attemp to create my own in xls.

What i'm referring to is the "Performance Estimate Procedure" under the Clariion Best Practices guide. It lists 1)Determine the workload, 2)Determine the disk load, 3)Determine number of disk drives required 4)Determine number and type of storage systems. I would think EMC would have one available to share to their customers?

driskollt1

131 Posts

December 16th, 2009 08:00

I keep a spreadsheet handy just for quick reference with the amount of IOPS a raid group can handle given the write profile, raid type, and # of disks.  I've included that.  I find it easier than doing the math every time.

  I'd look at analyzer (LUN Level) and see what your read/write ratio is on average.  I'd also probably look the LUN to see the throughput (IOPS) of the LUN.  I'd also check response time of the LUN and make sure it's an acceptable response time.  If not, more spindles might be needed.

The formula I use to calculate IOPS for a given # of disks is.

IOPS = SingleDiskIOPS * #OfDisks / (ReadRatio + (WritePenalty * WriteRatio)

RAID 5 = 4 write penalty

RAID 10 = 2 write penalty

I use 180 IOPS for 15k rpm and 130 for 10k RPM drives.

i.e Raid5 with 5 disks 20% write 15k rpm drives

(180 * 5) / (.8 + (.2 *4)) = 562.5 IOPS

If you're doing MetaLUNs, calculate the IOPS for 1 RAID group, then just multiply that by the # of RAID groups the MetaLUN spans.

Fibre Channel 15k Fibre Channel 10k
Disk Count R5 100% Write Available IOPS R5 100% Read Available IOPS R5 20% Write 80% Read Available IOPS R5 33% Write 67% Read Available IOPS R1+0 100% Write Available IOPS R1+0 100% Read Available IOPS R1+0 20% Write 80% Read Available IOPS R1+0 33% Write 67% Read Available IOPS R5 100% Write Available IOPS R5 100% Read Available IOPS R5 20% Write 80% Read Available IOPS R5 33% Write 67% Read Available IOPS R1+0 100% Write Available IOPS R1+0 100% Read Available IOPS R1+0 20% Write 80% Read Available IOPS R1+0 33% Write 67% Read Available IOPS
2 180 360 300.00 270.68 130 260 216.67 195.49
3 135 540 337.50 271.36 97.5 390 243.75 195.98
4 180 720 450.00 361.81 360 720 600.00 541.35 130 520 325.00 261.31 260 520 433.33 390.98
5 225 900 562.50 452.26 162.5 650 406.25 326.63
6 270 1080 675.00 542.71 540 1080 900.00 812.03 195 780 487.50 391.96 390 780 650.00 586.47
7 315 1260 787.50 633.17 227.5 910 568.75 457.29
8 360 1440 900.00 723.62 720 1440 1200.00 1082.71 260 1040 650.00 522.61 520 1040 866.67 781.95
9 405 1620 1012.50 814.07 292.5 1170 731.25 587.94
10 450 1800 1125.00 904.52 900 1800 1500.00 1353.38 325 1300 812.50 653.27 650 1300 1083.33 977.44
11 495 1980 1237.50 994.97 357.5 1430 893.75 718.59
12 540 2160 1350.00 1085.43 1080 2160 1800.00 1624.06 390 1560 975.00 783.92 780 1560 1300.00 1172.93
13 585 2340 1462.50 1175.88 422.5 1690 1056.25 849.25
14 630 2520 1575.00 1266.33 1260 2520 2100.00 1894.74 455 1820 1137.50 914.57 910 1820 1516.67 1368.42

kelleg

4.5K Posts

February 15th, 2010 10:00

Be careful about metaLUN performance - it's more complicated than just taking the number of components - you have to consider raid type, number of disks in the underlying raid groups, whether or not you're reusing the same raid group (not generally a good idea), etc.

glen

odurasler

103 Posts

February 15th, 2010 10:00

great info!

pharford57

115 Posts

March 3rd, 2011 07:00

Does anyone have any details on the VNX performance pleaseeeeee

telling people its 3 times faster than the clariion with ouit some detail is not working with customers :-)

View More

View All

No Events found!

Top