Bug 623595
| Summary: | move iscsi/iser to passthrough mode, fix functioning and failover time under DM multipath | ||||||
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| Product: | Red Hat Enterprise Linux 5 | Reporter: | Or Gerlitz <ogerlitz> | ||||
| Component: | kernel | Assignee: | Mike Christie <mchristi> | ||||
| Status: | CLOSED ERRATA | QA Contact: | Storage QE <storage-qe> | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | low | ||||||
| Version: | 5.6 | CC: | bdonahue, cward, mchristi | ||||
| Target Milestone: | rc | ||||||
| Target Release: | --- | ||||||
| Hardware: | All | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2011-01-13 21:09:41 UTC | Type: | --- | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Attachments: |
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Forgot to mention that the patch was generated against / tested with kernel 2.6.18-211.el5 This seems fine to me. It is upstream, Voltaire is doing testing, and they made the patch for us. Adding devel ack. Thanks Or. This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release. in kernel-2.6.18-219.el5 You can download this test kernel from http://people.redhat.com/jwilson/el5 Detailed testing feedback is always welcomed. An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2011-0017.html |
Created attachment 438383 [details] patch which has the related fixes from upstream Description of problem: Remove some inefficiencies in the iser data path through simplification and reducing the amount of code, using less atomic operations, avoiding TX interrupts, moving to iscsi passthrough mode, etc. As a result I was able to duplicate the amount of IOPS, upto about 300K and to reduce the latency measured through iostat AWAIT report. The upstream submission was done through a sequence of patches and not as one big re-write, to ease with maintainance and tuning. Fix bugs in the disconnection logic of iser which made the failover time with dm-multipathing to be too long, at least 120 seconds, wheres now it can get to be 30 seconds and below that. This part is the same as RHEL6 bugzilla 589174 Attached is the patch which addresses all that.