db: add tests for EstimateDiskUsage

[Sachuman]

Added tests for EstimateDiskUsage and EstimateDiskUsageByBackingType.
Added calls to metamorphic tests, not for results but for races/panics.

Implements #5235

[cockroach-teamcity]

This change is 

[jbowens]

@jbowens reviewed 6 of 7 files at r1, all commit messages.
Reviewable status: 6 of 7 files reviewed, 2 unresolved discussions (waiting on @xxmplus)

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disk_usage_test.go line 155 at r1 (raw file):

				case "zero":
					require.Equal(t, uint64(0), total)
				case "non-zero":

rather than just expecting zero or nonzero, can we include an explicit value in the test results? It'll help catch instances where the calculated size changes unexpected/unintentionally.

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metamorphic/generator.go line 418 at r1 (raw file):

}

func (g *generator) dbEstimateDiskUsage() {

nice

[RaduBerinde]

Very nice!

Reviewable status: 6 of 7 files reviewed, 2 unresolved discussions (waiting on @jbowens, @Sachuman, and @xxmplus)

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disk_usage_test.go line 155 at r1 (raw file):

Previously, jbowens (Jackson Owens) wrote…

rather than just expecting zero or nonzero, can we include an explicit value in the test results? It'll help catch instances where the calculated size changes unexpected/unintentionally.

+1 We'll probably need to set DisableAutomaticCompactions in the options.

[Sachuman]

Reviewable status: 5 of 7 files reviewed, 2 unresolved discussions (waiting on @jbowens and @xxmplus)

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disk_usage_test.go line 155 at r1 (raw file):

Previously, RaduBerinde wrote…

+1 We'll probably need to set DisableAutomaticCompactions in the options.

Seems like even after DisableAutomaticCompactions set, for ingest-external, there is non-determinism for the size,
So I added the expect parameter as optional.

[RaduBerinde]

Reviewable status: 5 of 7 files reviewed, 2 unresolved discussions (waiting on @jbowens, @Sachuman, and @xxmplus)

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disk_usage_test.go line 155 at r1 (raw file):

Previously, Sachuman (Sachin) wrote…

Seems like even after DisableAutomaticCompactions set, for ingest-external, there is non-determinism for the size,
So I added the expect parameter as optional.

There are other tests that use ingestions and are deterministic. I think we need to specify the block sizes to avoid the randomization in runBuildRemoteCmd

If it still doesn't work, instead of expect-total you can add a flag that changes any non-zero value to a special <non-zero> string when outputting (so we can continue to rely on matching test output)

[Sachuman]

Reviewable status: 5 of 7 files reviewed, 2 unresolved discussions (waiting on @jbowens and @xxmplus)

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disk_usage_test.go line 155 at r1 (raw file):

Previously, RaduBerinde wrote…

There are other tests that use ingestions and are deterministic. I think we need to specify the block sizes to avoid the randomization in runBuildRemoteCmd

If it still doesn't work, instead of expect-total you can add a flag that changes any non-zero value to a special <non-zero> string when outputting (so we can continue to rely on matching test output)

Specifying the block size worked, I did not realize it was random there. Thanks

[jbowens]

Reviewable status: 5 of 7 files reviewed, 2 unresolved discussions (waiting on @Sachuman and @xxmplus)

[Sachuman]

TFTRs!