Fibre Channel (SAN)

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Occasional Contributor
Posts: 17
Registered: ‎10-09-2014

Re: Has anyone seen an increase in High Bandwidth following upgrade to v7.4.0a?

Re anovelli:

 

Thanks for the suggestion.  Just taken a look through the various 7.2, 7.3 and 7.4 release notes, and haven't found anything I think is relevant.

 

In the spirit of really thinking outside the box though, I copied some things that are kind of relevant, in case anyone here thinks they might be - I'd be suprised if this were the case tho:

 

 

FOS v7.2 allows buffer credit assignment even for “normal distance” (regular) E_ports

  • The portCfgEportCredits CLI introduced in FOS v7.2 allows users to perform fine grained performancetuning on normal E_ports by allowing users to specify buffer credits.  

(We have E-Port Credit Configuration is not Enabled)

 

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FOS v7.2 introduces a new CLI “creditrecovmode” to configure backend link credit loss recovery options

  • Existing credit loss recovery options of the bottleneckmon CLI continue to be supported in FOS v7.2 but will be removed from FOS v7.3.
  • Simplifies the bottleneckmon CLI.

bottleneckMon CLI Change  

FOS v7.3 deprecates the back-end credit recovery options in the bottleneckMon CLI. These options are supported via the existing creditRecovMode CLI.

 

(we have:

    Internal port credit recovery is Enabled with LrOnly

    Back end port Loss of Sync's Link Reset is Disabled

    C2 FE Complete Credit Loss Detection is Disabled)

 

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E_Port Balance Priority Routing

FOS v7.3 enhances routing policy with the E_Port Balance Priority option. With this enhancement, when multiple paths to a domain exist, routing policy would assign routes so that the bandwidth demands from source ports are evenly distributed among all E_Ports.

 

(we have E_Port Balance Priority not set)

 

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Link Reset on Loss of Sync

FOS v7.4 enhances credit recovery on backend links for 8G platforms by performing link reset (LR) on loss of sync (LOS) events. This enhancements applies to a port where a loss of sync is detected and the peer port of the backend link is on a 8G platform.

Frequent Contributor
Posts: 112
Registered: ‎04-05-2011

Re: Has anyone seen an increase in High Bandwidth following upgrade to v7.4.0a?

Hello johnnylawes,

 

  • about the portcfgeportcredits, it is just relevant if you changed those parameters, otherwise it was not changed from previous settings.

 

  • creditrecovmode and bottleneckmon --credittools can increase performance and resiliency on internal backlinks but it raises specific messages on Raslog when it acts. And just makes sense if your backlinks were saturated ( look for traffic cossing from blade 1 to 8 in both directions).

Antonio's suggestion (sanhealth) is a good heading to follow.

 

 

BUT, as important as the improvements, are the defects found and closed in each release. Looking at the FOS 7.4 release notes, there are some issues related to MAPS. One of them related to High usage reports in MAPS dashboards. I noticed two points above 100% in you attached graphic chart and it is the symptom of DEFECT000525068.

 

 

Contributor
Posts: 33
Registered: ‎08-15-2007

Re: Has anyone seen an increase in High Bandwidth following upgrade to v7.4.0a?

[ Edited ]

Our reports were too big so I had to run a SAN health without performance stats.

External Moderator
Posts: 5,307
Registered: ‎02-23-2004

Re: Has anyone seen an increase in High Bandwidth following upgrade to v7.4.0a?

Tony,

 

please take a look in you company email account.

TechHelp24
Regular Contributor
Posts: 166
Registered: ‎02-05-2014

Re: Has anyone seen an increase in High Bandwidth following upgrade to v7.4.0a?

To be fairly honest unless you've seen an unusual drop in tx_crdt_timeout there is not an indication that different FOS code versions allow for an increase in bandwidth. I would start investigating the workload from a host perspective and correlate that to the numbers seen in the switch.

 

That being said the granularity of which MAPS is reporting on performance numers has significantly improved and may cause the increase in the total numer of events. Previous versions of fabricwatch did average out over a longer timeframe whereas MAPS with FPI is monitoring on a 2.5us interval. FOS 7.2 and up could report on sub-seconf latency but this had to be manually configured via the "bottleneckmon" command.

 

As you mentioned the phenomenon is simply a reporting observation and not related to a performance problem perse.

 

 

Kind regards,
Erwin van Londen
Brocade Distinguished Architect
http://www.erwinvanlonden.net The Fibre Channel blog



Q&A -> https://hackhands.com/elo/


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External Moderator
Posts: 5,307
Registered: ‎02-23-2004

Re: Has anyone seen an increase in High Bandwidth following upgrade to v7.4.0a?

[ Edited ]

if has given one command in FOS that was ever miscarriage, then a command is called "bottleneckmon"

as per my opinion, that command shold never existed.

......but as I said, is just my opinion

TechHelp24

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