Fix(Dgraph): Throttle number of files to open while schema update #7480
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vmrajas
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manishrjain and
vvbalaji-dgraph
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NamanJain8
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Feb 24, 2021
worker/mutation.go
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| maxOpenFileLimit = 1024 | ||
| } | ||
| glog.Infof("Max open files limit: %d", maxOpenFileLimit) | ||
| // Badger opens around 7 files for indexing per predicate. |
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How did you calculate the number 7?
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This PR to address the error of "Too many open files" on empty database. I arrived at this number to account for the files, MANIFEST, LOCK, KEYREGISTRY, DISCARD, 00001.mem and 00001.vlog
jarifibrahim
suggested changes
Feb 25, 2021
jarifibrahim
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Mar 3, 2021
abhimanyusinghgaur
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Mar 3, 2021
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Motivation:
Currently, while doing GraphQL schema update, many files are opened simultaneously for the purpose of indexing predicates. This may create a problem and throw error, "Too many open files" if ulimit is not set properly.
This PR fixes this and puts a limit on the number of threads which create and open files.
Note that this is only meant to address this problem on an empty database. The error may still be thrown (with lower frequency) if the schema update is done on a large dataset.
Testing:
This change is