ENT-6511: Increase cf-monitord measurement slots from 100 to 300#6239
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ENT-6511: Increase cf-monitord measurement slots from 100 to 300#6239nickanderson wants to merge 2 commits into
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~80 of the 100 slots are consumed by default measurements, leaving little room for custom ones. Raise the limit to 300. Kept in sync: CF_OBSERVABLES and the two cf-check copies of the on-disk struct, plus the OBSERVABLES name table (GetObservable() indexes it for unregistered slots, so a short table crashes cf-monitord). cf-check dump now tolerates the shorter records and ts_key a pre-upgrade agent leaves behind. Ticket: ENT-6511 Changelog: Increased the maximum number of cf-monitord measurement slots (CF_OBSERVABLES) from 100 to 300
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@cf-bottom jenkins please. |
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Sure, I triggered a build: Jenkins: https://ci.cfengine.com/job/pr-pipeline/14244/ Packages: http://buildcache.cfengine.com/packages/testing-pr/jenkins-pr-pipeline-14244/ |
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| // A record written before an increase of CF_OBSERVABLES is shorter than the | ||
| // current struct (e.g. after a package upgrade, until cf-monitord rewrites | ||
| // it). Accept any size up to the full struct and copy into a zeroed struct | ||
| // so the un-stored trailing slots read back as zero. |
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Please try to do a DB migration like libpromises/dbm_migration_lastseen.c instead if its possible.
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OK ... this makes me wonder about the other DB backends like tcdb and qmdb and bdb, those aren't covered at all. I guess that's ok we don't vendor any packages with those
Raising CF_OBSERVABLES enlarges the fixed-size Averages record, so records written by an older agent are shorter than the current struct. Added a migration (modelled on dbm_migration_lastseen.c) that rewrites old records to the current size, zero-filling the new slots, registered for the observations and history DBs. This replaces the cf-check dump leniency with a one-time on-disk migration; dump only needs to know the new "version" key. Ticket: ENT-6511 Changelog: None
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@cf-bottom jenkins please. |
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Alright, I triggered a build: Jenkins: https://ci.cfengine.com/job/pr-pipeline/14253/ Packages: http://buildcache.cfengine.com/packages/testing-pr/jenkins-pr-pipeline-14253/ |
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Raises
CF_OBSERVABLESfrom 100 to 300. Previously out of the box ~80 of the 100 slots are consumed by default measurements, leaving only ~19 for custommeasurements:promises.Notably, this change does increase the disk footprint required by an agent by
60MB (.27MB per slot). That storage is required even if the slots are not in active use (Ref: ENT-14329)Ticket: ENT-6511