Bug 191531
| Summary: | kernel dm snapshot: ENOMEM after a number of snapshots | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Brian J. Murrell <brian> |
| Component: | device-mapper-obsolete | Assignee: | Milan Broz <mbroz> |
| Status: | CLOSED DUPLICATE | QA Contact: | |
| Severity: | high | Docs Contact: | |
| Priority: | medium | ||
| Version: | rawhide | CC: | agk, christophe.varoqui, dmilburn, dwysocha, egoggin, lmb, mbroz, pvrabec, tranlan |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2007-06-13 16:10:49 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: | |||
Description of problem: Version-Release number of selected component (if applicable): device-mapper-1.01.02-1.0 How reproducible: 100% Steps to Reproduce: 1. Create a pv, vg and finaly an lv, let's call it "test". then 2. for x in $(seq 1 20); do lvcreate -s -L1G -n test$x /dev/vg/test || break done On my local system I get an ENOMEM after about 16 snapshots. Expected results: Many more snapsots, not limited by the maximum size of a single kmalloc. Additional info: We have managed to trace the problem to the use of mempools for the _io_pool and that adding snspshots requires the pool be grown, which ends up hitting the limits that kmalloc() imposes on allocations. Is this a known limitiation? Are there any plans to solve/eliminate it? If somebody were to take on reworking that area of code/design, do you have any preferences or designs in how it is done?