Move all cases of direct "engine" access to inline-MVCC.#185
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spencerkimball merged 1 commit intomasterfrom Nov 25, 2014
Merged
Move all cases of direct "engine" access to inline-MVCC.#185spencerkimball merged 1 commit intomasterfrom
spencerkimball merged 1 commit intomasterfrom
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This is a necessary step towards ranges which will contain time series data, which requires merging. Efficient merging cannot be done using our multi-row MVCC model. This change provides an inline value in the MVCCMetadata which is used instead of a versioned value if the timestamp is specified as zero. Inline values are replaced on successive puts and are cleared on deletes. The inlined values can be accessed just like versioned values, and all MVCC operations work, modulo differences in how timestamps are interpreted. Once a value has been written as inline, it may not be overwritten using a timestamp for version values. Inlined values support merge. Currently, the stats are inaccurately kept for merge, though the next change will do benchmarks to ascertain the cost of keeping accurate stats.
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Fairly straightforward, LGTM |
spencerkimball
added a commit
that referenced
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Nov 25, 2014
Move all cases of direct "engine" access to inline-MVCC.
tbg
referenced
this pull request
in tbg/cockroach
Aug 31, 2016
We have been seeing long startup times which disappear spontaneously. During a
restart of the beta cluster, the following goroutine was observed, which suggests
that we were spending a lot of time GCing replicas on startup.
engine ??:0 _Cfunc_DBIterNext(cockroachdb#324, cockroachdb#323, 0, 0, 0, 0, 0, 0, 0)
engine rocksdb.go:1135 (*rocksDBIterator).Next(cockroachdb#235)
storage replica_data_iter.go:104 (*ReplicaDataIterator).Next(cockroachdb#316)
storage store.go:1748 (*Store).destroyReplicaData(#109, cockroachdb#317, 0, 0)
storage store.go:841 (*Store).Start.func2(0x101b, cockroachdb#300, 0x36, 0x40, cockroachdb#301, 0x36, 0x40, cockroachdb#315, 0x3, 0x4, ...)
storage store.go:734 IterateRangeDescriptors.func1(cockroachdb#306, 0x40, 0x41, cockroachdb#307, 0x92, 0x92, cockroachdb#341, 0, 0x186c, 0x4000, ...)
engine mvcc.go:1593 MVCCIterate(cockroachdb#329, #68, #47, #81, cockroachdb#232, 0x9, 0x10, cockroachdb#233, 0xb, 0x10, ...)
storage store.go:738 IterateRangeDescriptors(cockroachdb#330, cockroachdb#196, #47, #81, cockroachdb#195, #179, #110)
storage store.go:867 (*Store).Start(#109, cockroachdb#330, cockroachdb#196, #179, #185, 0x1)
server node.go:405 (*Node).initStores(#78, cockroachdb#330, cockroachdb#196, #98, 0x1, 0x1, #179, 0, #55)
server node.go:330 (*Node).start(#78, cockroachdb#330, cockroachdb#196, #42, #129, #98, 0x1, 0x1, 0, 0, ...)
server server.go:431 (*Server).Start(#5, cockroachdb#330, cockroachdb#196, #95, 0x1)
cli start.go:368 runStart(#34, #178, 0, 0x9, 0, 0)
cobra command.go:599 (*Command).execute(#34, #177, 0x9, 0x9, #34, #177)
cobra command.go:689 (*Command).ExecuteC(#33, #70, cockroachdb#343, #72)
cobra command.go:648 (*Command).Execute(#33, #71, cockroachdb#343)
cli cli.go:96 Run(#64, 0xa, 0xa, 0, 0)
main main.go:37 main()
tbg
referenced
this pull request
in tbg/cockroach
Aug 31, 2016
We have been seeing long startup times which disappear spontaneously. During a
restart of the beta cluster, the following goroutine was observed, which suggests
that we were spending a lot of time GCing replicas on startup.
engine ??:0 _Cfunc_DBIterNext(cockroachdb#324, cockroachdb#323, 0, 0, 0, 0, 0, 0, 0)
engine rocksdb.go:1135 (*rocksDBIterator).Next(cockroachdb#235)
storage replica_data_iter.go:104 (*ReplicaDataIterator).Next(cockroachdb#316)
storage store.go:1748 (*Store).destroyReplicaData(#109, cockroachdb#317, 0, 0)
storage store.go:841 (*Store).Start.func2(0x101b, cockroachdb#300, 0x36, 0x40, cockroachdb#301, 0x36, 0x40, cockroachdb#315, 0x3, 0x4, ...)
storage store.go:734 IterateRangeDescriptors.func1(cockroachdb#306, 0x40, 0x41, cockroachdb#307, 0x92, 0x92, cockroachdb#341, 0, 0x186c, 0x4000, ...)
engine mvcc.go:1593 MVCCIterate(cockroachdb#329, #68, #47, #81, cockroachdb#232, 0x9, 0x10, cockroachdb#233, 0xb, 0x10, ...)
storage store.go:738 IterateRangeDescriptors(cockroachdb#330, cockroachdb#196, #47, #81, cockroachdb#195, #179, #110)
storage store.go:867 (*Store).Start(#109, cockroachdb#330, cockroachdb#196, #179, #185, 0x1)
server node.go:405 (*Node).initStores(#78, cockroachdb#330, cockroachdb#196, #98, 0x1, 0x1, #179, 0, #55)
server node.go:330 (*Node).start(#78, cockroachdb#330, cockroachdb#196, #42, #129, #98, 0x1, 0x1, 0, 0, ...)
server server.go:431 (*Server).Start(#5, cockroachdb#330, cockroachdb#196, #95, 0x1)
cli start.go:368 runStart(#34, #178, 0, 0x9, 0, 0)
cobra command.go:599 (*Command).execute(#34, #177, 0x9, 0x9, #34, #177)
cobra command.go:689 (*Command).ExecuteC(#33, #70, cockroachdb#343, #72)
cobra command.go:648 (*Command).Execute(#33, #71, cockroachdb#343)
cli cli.go:96 Run(#64, 0xa, 0xa, 0, 0)
main main.go:37 main()
pav-kv
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to pav-kv/cockroach
that referenced
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Apr 10, 2024
…h-assert-(raft_flow_control_test.go) Test: Replace t.error/fatal with assert/request in [raft_flow_control_test.go]
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This is a necessary step towards ranges which will contain time series
data, which requires merging. Efficient merging cannot be done using
our multi-row MVCC model. This change provides an inline value in the
MVCCMetadata which is used instead of a versioned value if the timestamp
is specified as zero. Inline values are replaced on successive puts and
are cleared on deletes.
The inlined values can be accessed just like versioned values, and all
MVCC operations work, modulo differences in how timestamps are interpreted.
Once a value has been written as inline, it may not be overwritten using
a timestamp for version values. Inlined values support merge.
Currently, the stats are inaccurately kept for merge, though the next
change will do benchmarks to ascertain the cost of keeping accurate
stats.