Bug 1348068
| Summary: | High i/o latency with random write workload from virtual machine(s) | ||||||||
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| Product: | [Community] GlusterFS | Reporter: | Paul Cuzner <pcuzner> | ||||||
| Component: | replicate | Assignee: | Krutika Dhananjay <kdhananj> | ||||||
| Status: | CLOSED EOL | QA Contact: | |||||||
| Severity: | medium | Docs Contact: | |||||||
| Priority: | medium | ||||||||
| Version: | 3.7.9 | CC: | bugs, mliyazud, pkarampu | ||||||
| Target Milestone: | --- | Keywords: | Triaged | ||||||
| Target Release: | --- | ||||||||
| Hardware: | x86_64 | ||||||||
| OS: | Linux | ||||||||
| Whiteboard: | |||||||||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |||||||
| Doc Text: | Story Points: | --- | |||||||
| Clone Of: | |||||||||
| : | 1392419 (view as bug list) | Environment: | |||||||
| Last Closed: | 2017-03-08 11:03:38 UTC | Type: | Bug | ||||||
| Regression: | --- | Mount Type: | --- | ||||||
| Documentation: | --- | CRM: | |||||||
| Verified Versions: | Category: | --- | |||||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||||
| Embargoed: | |||||||||
| Bug Depends On: | |||||||||
| Bug Blocks: | 1392419 | ||||||||
| Attachments: |
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Created attachment 1169677 [details]
screenshot showing the max latency at 4secs within the iometer run
Added a screenshot showing the max latency observed from the iometer run. This is from a single vm running the workload (as per the icf file attached to the case)
This bug is getting closed because GlusteFS-3.7 has reached its end-of-life. Note: This bug is being closed using a script. No verification has been performed to check if it still exists on newer releases of GlusterFS. If this bug still exists in newer GlusterFS releases, please reopen this bug against the newer release. |
Created attachment 1169665 [details] iometer config file Description of problem: When using either a replica 3 or sharded replica 3 volume with virtual machines, profiles that exhibit random writes cause high latencies than can sometimes span several seconds. This has been observed with both fio and iometer as load generators Sequential writes do NOT exhibit this affect Version-Release number of selected component (if applicable): How reproducible: Every time the workload is run this profile is observed Steps to Reproduce: 1. use either an fio workload with random write or an iometer profile (attached) 2. track the latency in the vm with pcp 3. Actual results: High latencies are observed which could impact application response times Expected results: Spikes in random write workloads are accepted - may be in the 10's of milliseconds - but latencies that are between 600ms 2s are a problem Additional info: