HP 3PAR Express Writes

© Copyright 2014 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice.© Copyright 2014 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice.

An overview of:

HP 3PAR Express Writes

Ivan IannacconeHP 3PAR Product Management

© Copyright 2014 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice.2

HP 3PAR

HP 3PAR Express Writes

Backend

• HP 3PAR OS changes to deliver lower CPU interrupts per I/O transaction.

• This results in higher IOPS and reduced latency for writes.

• Express Writes does not require any changes on the initators side.

• All supported HBAs and Hosts will benefit of this optimization.

Flash or HDD

Hosts

Optimized Writes –fewer interrupts

Cache

Fibre Channel protocol optimization

Optimized code


HP 3PAR Express Writes – Telemetry DataBelow we are showing Telemetry data from the 3PAR Install Base that compares the amount of write access below 1ms between 3.1.3 and 3.2.1 systems. The data highlighted in the rectangle shows how systems on 3.2.1 (Express Writes Enabled) are able to satisfy more write request in around 0.120ms (~40% vs 3.1.3 10%).


Express Writes – SSMC ReportPrior the 3.2.1 upgrade 90% of writes where committed in 0.250microseconds or more,10% where committed in 0.125 microseconds or less.After the upgrade to 3.2.1 around 50% of writes are now committed in 0.125 microseconds or less.

3.2.1 upgrade


Express Writes effect on 7450

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0.062 0.125 0.25 0.5

3.1.2 3.2.170% of Write IO occurred in 0.25 millisecond28% of Write IO occurred in 0.5 millisecond2% of Write IO occurred in 0.125 milliseconds0% of Write IO occurs in 0.062 milliseconds

45% of Write IO occurs in 0.125 milliseconds40% of Write IO occurs in 0.250 milliseconds10% of Write IO occurs in 0.50 milliseconds5% of Write IO occurs in 0.062 milliseconds

3.2.1 upgrade


Express Writes and Thin Deduplication

0.00%

20.00%

40.00%

60.00%

80.00%

100.00%

120.00%

0.062 0.125 0.25 0.5 1

Express Writes on AFA with Thin Deduplication

r w t

And to conclude we can also look at a system that was born on HP 3PAR OS 3.2.1 and running a VDI workload with Thinly Deduplicated Volumes (5:1 dedup), as you can see around 40% of write I/O is completed in 0.125 microseconds or less.

© Copyright 2014 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice.

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How to create a report:Look at 2 weeks prior and after the upgrade to 3.2.1 using daily sampling.

CLI (btsecs date in the below example is the time prior the upgrade and etsecs is the date 2 weeks after.For example if I upgraded on the 15th of November :

• srhistvlun -rw -timecols 4 5 -pct -daily -btsecs "2014-11-01" -etsecs "2014-11-30“

Import the data in excel, filter for the write column, select the 0.125 and 0.250 columns and create a chart over time!

SSMC

Go under System Reporter and select the Exported Volumes histogram template, select a time range of 2 weeks prior and 2 weeks after the upgrade of daily sampling. Select IO time values between 0.125 and 0.250 and writes as IO type.


Example on how to do a report in SSMC using Exported Volumes, IO Time template.

Pick a range using daily data, 1 week before and after the upgrade with chart option defined on the left.


Results may vary!

• Every workload is different so it’s possible not all systems will see the same benefits.

• Just keep that in mind and try other ‘buckets’ like 0.250 and 0.500 (instead than 0.125 and 0.250)

© Copyright 2014 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice.

Thank you

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HP 3PAR Express Writes