request only 1 best version for latest version resolution (#14625)

ListObjects, ListObjectsV2 calls are being heavily taxed when
there are many versions on objects left over from a previous
release or ILM was never setup to clean them up. Instead
of being absolutely correct at resolving the exact latest
version of an object, we simply rely on the top most 1
version and resolve the rest.

Once we have obtained the top most "1" version for
ListObject, ListObjectsV2 call we break out.
This commit is contained in:
Harshavardhana 2022-03-25 08:50:07 -07:00 committed by GitHub
parent 401958938d
commit f046f557fa
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GPG Key ID: 4AEE18F83AFDEB23
4 changed files with 98 additions and 16 deletions

View File

@ -281,10 +281,16 @@ func (m metaCacheEntries) shallowClone() metaCacheEntries {
}
type metadataResolutionParams struct {
dirQuorum int // Number if disks needed for a directory to 'exist'.
objQuorum int // Number of disks needed for an object to 'exist'.
bucket string // Name of the bucket. Used for generating cached fileinfo.
strict bool // Versions must match exactly, including all metadata.
dirQuorum int // Number if disks needed for a directory to 'exist'.
objQuorum int // Number of disks needed for an object to 'exist'.
// An optimization request only an 'n' amount of versions from xl.meta
// to avoid resolving all versions to figure out the latest 'version'
// for ListObjects, ListObjectsV2
requestedVersions int
bucket string // Name of the bucket. Used for generating cached fileinfo.
strict bool // Versions must match exactly, including all metadata.
// Reusable slice for resolution
candidates [][]xlMetaV2ShallowVersion
@ -372,7 +378,7 @@ func (m metaCacheEntries) resolve(r *metadataResolutionParams) (selected *metaCa
reusable: true,
cached: &xlMetaV2{metaV: selected.cached.metaV},
}
selected.cached.versions = mergeXLV2Versions(r.objQuorum, r.strict, r.candidates...)
selected.cached.versions = mergeXLV2Versions(r.objQuorum, r.strict, r.requestedVersions, r.candidates...)
if len(selected.cached.versions) == 0 {
return nil, false
}

View File

@ -571,6 +571,13 @@ func (er *erasureObjects) listPath(ctx context.Context, o listPathOptions, resul
bucket: o.Bucket,
}
// Maximum versions requested for "latest" object
// resolution on versioned buckets, this is to be only
// used when o.Versioned is false
if !o.Versioned {
resolver.requestedVersions = 1
}
ctxDone := ctx.Done()
return listPathRaw(ctx, listPathRawOptions{
disks: disks,

View File

@ -1691,7 +1691,7 @@ func (x xlMetaV2) ListVersions(volume, path string) ([]FileInfo, error) {
// Quorum must be the minimum number of matching metadata files.
// Quorum should be > 1 and <= len(versions).
// If strict is set to false, entries that match type
func mergeXLV2Versions(quorum int, strict bool, versions ...[]xlMetaV2ShallowVersion) (merged []xlMetaV2ShallowVersion) {
func mergeXLV2Versions(quorum int, strict bool, requestedVersions int, versions ...[]xlMetaV2ShallowVersion) (merged []xlMetaV2ShallowVersion) {
if quorum <= 0 {
quorum = 1
}
@ -1708,6 +1708,8 @@ func mergeXLV2Versions(quorum int, strict bool, versions ...[]xlMetaV2ShallowVer
// Shallow copy input
versions = append(make([][]xlMetaV2ShallowVersion, 0, len(versions)), versions...)
var nVersions int // captures all non-free versions
// Our result
merged = make([]xlMetaV2ShallowVersion, 0, len(versions[0]))
tops := make([]xlMetaV2ShallowVersion, len(versions))
@ -1744,6 +1746,12 @@ func mergeXLV2Versions(quorum int, strict bool, versions ...[]xlMetaV2ShallowVer
latest = tops[0]
latestCount = len(tops)
merged = append(merged, latest)
// Calculate latest 'n' non-free versions.
if !latest.header.FreeVersion() {
nVersions++
}
} else {
// Find latest.
for i, ver := range tops {
@ -1807,6 +1815,11 @@ func mergeXLV2Versions(quorum int, strict bool, versions ...[]xlMetaV2ShallowVer
}
if latestCount >= quorum {
merged = append(merged, latest)
// Calculate latest 'n' non-free versions.
if !latest.header.FreeVersion() {
nVersions++
}
}
}
@ -1840,7 +1853,13 @@ func mergeXLV2Versions(quorum int, strict bool, versions ...[]xlMetaV2ShallowVer
break
}
}
if requestedVersions > 0 && requestedVersions == nVersions {
merged = append(merged, versions[0]...)
break
}
}
// Sanity check. Enable if duplicates show up.
if false {
found := make(map[[16]byte]struct{})

View File

@ -401,6 +401,55 @@ func TestDeleteVersionWithSharedDataDir(t *testing.T) {
}
}
func Benchmark_mergeXLV2Versions(b *testing.B) {
data, err := ioutil.ReadFile("testdata/xl.meta-v1.2.zst")
if err != nil {
b.Fatal(err)
}
dec, _ := zstd.NewReader(nil)
data, err = dec.DecodeAll(data, nil)
if err != nil {
b.Fatal(err)
}
var xl xlMetaV2
if err = xl.LoadOrConvert(data); err != nil {
b.Fatal(err)
}
vers := make([][]xlMetaV2ShallowVersion, 16)
for i := range vers {
vers[i] = xl.versions
}
b.Run("requested-none", func(b *testing.B) {
b.ReportAllocs()
b.ResetTimer()
b.SetBytes(855) // number of versions...
for i := 0; i < b.N; i++ {
mergeXLV2Versions(8, false, 0, vers...)
}
})
b.Run("requested-v1", func(b *testing.B) {
b.ReportAllocs()
b.ResetTimer()
b.SetBytes(855) // number of versions...
for i := 0; i < b.N; i++ {
mergeXLV2Versions(8, false, 1, vers...)
}
})
b.Run("requested-v2", func(b *testing.B) {
b.ReportAllocs()
b.ResetTimer()
b.SetBytes(855) // number of versions...
for i := 0; i < b.N; i++ {
mergeXLV2Versions(8, false, 1, vers...)
}
})
}
func Benchmark_xlMetaV2Shallow_Load(b *testing.B) {
data, err := ioutil.ReadFile("testdata/xl.meta-v1.2.zst")
if err != nil {
@ -424,6 +473,7 @@ func Benchmark_xlMetaV2Shallow_Load(b *testing.B) {
}
}
})
b.Run("indexed", func(b *testing.B) {
var xl xlMetaV2
err = xl.Load(data)
@ -550,7 +600,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
for i := range vers {
t.Run(fmt.Sprintf("non-strict-q%d", i), func(t *testing.T) {
merged := mergeXLV2Versions(i, false, vers...)
merged := mergeXLV2Versions(i, false, 0, vers...)
if len(merged) == 0 {
t.Error("Did not get any results")
return
@ -562,7 +612,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
})
t.Run(fmt.Sprintf("strict-q%d", i), func(t *testing.T) {
merged := mergeXLV2Versions(i, true, vers...)
merged := mergeXLV2Versions(i, true, 0, vers...)
if len(merged) == 0 {
t.Error("Did not get any results")
return
@ -584,7 +634,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, false, vMod...)
merged := mergeXLV2Versions(i, false, 0, vMod...)
if len(merged) == 0 {
t.Error("Did not get any results")
return
@ -606,7 +656,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, false, vMod...)
merged := mergeXLV2Versions(i, false, 0, vMod...)
if len(merged) == 0 && i < 2 {
t.Error("Did not get any results")
return
@ -632,7 +682,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, false, vMod...)
merged := mergeXLV2Versions(i, false, 0, vMod...)
if len(merged) == 0 {
t.Error("Did not get any results")
return
@ -654,7 +704,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, false, vMod...)
merged := mergeXLV2Versions(i, false, 0, vMod...)
if len(merged) == 0 && i < 2 {
t.Error("Did not get any results")
return
@ -680,7 +730,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, true, vMod...)
merged := mergeXLV2Versions(i, true, 0, vMod...)
if len(merged) == 0 && i < 2 {
t.Error("Did not get any results")
return
@ -706,7 +756,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, true, vMod...)
merged := mergeXLV2Versions(i, true, 0, vMod...)
if len(merged) == 0 && i < 2 {
t.Error("Did not get any results")
return
@ -732,7 +782,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, true, vMod...)
merged := mergeXLV2Versions(i, true, 0, vMod...)
if len(merged) == 0 && i < 2 {
t.Error("Did not get any results")
return
@ -758,7 +808,7 @@ func Test_mergeXLV2Versions(t *testing.T) {
}
vMod = append(vMod, newVers)
}
merged := mergeXLV2Versions(i, true, vMod...)
merged := mergeXLV2Versions(i, true, 0, vMod...)
if len(merged) == 0 && i < 2 {
t.Error("Did not get any results")
return