Hana McLaughlin

The vdo config info : config: !Configuration vdos: dataDB: !VDOService _operationState: finished ackThreads: 2 activated: enabled bioRotationInterval: 64 bioThreads: 6 blockMapCacheSize: 128M blockMapPeriod: 16380 compression: enabled cpuThreads: 6 deduplication: enabled...

@lorelei-sakai I did see similar kinds of crash stack several times on different kernel versions and vdo versions. The kernel version 3.10 and 4.19, vdo version 6.1.1.125， 6.1.3.23 and 6.2.6...

@raeburn @sweettea The [issue-46](https://github.com/dm-vdo/kvdo/issues/46) with the simliar list_del corruption with vdo version 6.1 on kernel 3.10. But no luck, without vmcore generated because the system was hanged.

@raeburn @lorelei-sakai @sweettea Please let me know if you need any other information.

[vmcore-demsg.zip](https://github.com/dm-vdo/kvdo/files/8332305/vmcore-demsg.zip) Here is the vmcore-demsg from the machine running Vdo 6.1 on kernel 3.10. Hope it's useful !

@raeburn @sweettea How to avoid this problem? Can you give some advices? I try to reduce vdo threads , but the problem still occured. vdo modify --all --vdoAckThreads=1 --vdoBioThreads=2 --vdoCpuThreads=1...

Thank you very much for your reply!

> Raising the timeout can reduce throughput if VDO (specifically the UDS index portion) is being slow for some reason. On the other hand, if it’s taking much more than...

@raeburn Thank you very much! I will test the fix. https://github.com/dm-vdo/kvdo/commit/72f94c2d858e4baabeba72bc3551287a2dd45d87

@raeburn The kvdo 6.2 version hang my system occasionally. My system runs 4.19 kernel. The problem always occurs when reading a lot.