minio/cmd/disk-cache_test.go
poornas 224b4f13b8
Add cache eviction low and high watermarks (#8958)
To allow better control the cache eviction process.

Introduce MINIO_CACHE_WATERMARK_LOW and 
MINIO_CACHE_WATERMARK_HIGH env. variables to specify 
when to stop/start cache eviction process. 

Deprecate MINIO_CACHE_EXPIRY environment variable. Cache 
gc sweeps at 30 minute intervals whenever high watermark is
reached to clear least recently accessed entries in the cache
until sufficient space is cleared to reach the low watermark.

Garbage collection uses an adaptive file scoring approach based
on last access time, with greater weights assigned to larger
objects and those with more hits to find the candidates for eviction.

Thanks to @klauspost for this file scoring algorithm

Co-authored-by: Klaus Post <klauspost@minio.io>
2020-02-23 19:03:39 +05:30

336 lines
9.2 KiB
Go

/*
* MinIO Cloud Storage, (C) 2018,2019 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cmd
import (
"bytes"
"context"
"io"
"net/http"
"testing"
"github.com/minio/minio/pkg/hash"
)
// Initialize cache objects.
func initCacheObjects(disk string, cacheMaxUse, cacheAfter, cacheWatermarkLow, cacheWatermarkHigh int) (*diskCache, error) {
return newDiskCache(disk, cacheMaxUse, cacheAfter, cacheWatermarkLow, cacheWatermarkHigh)
}
// inits diskCache struct for nDisks
func initDiskCaches(drives []string, cacheMaxUse, cacheAfter, cacheWatermarkLow, cacheWatermarkHigh int, t *testing.T) ([]*diskCache, error) {
var cb []*diskCache
for _, d := range drives {
obj, err := initCacheObjects(d, cacheMaxUse, cacheAfter, cacheWatermarkLow, cacheWatermarkHigh)
if err != nil {
return nil, err
}
cb = append(cb, obj)
}
return cb, nil
}
// Tests ToObjectInfo function.
func TestCacheMetadataObjInfo(t *testing.T) {
m := cacheMeta{Meta: nil}
objInfo := m.ToObjectInfo("testbucket", "testobject")
if objInfo.Size != 0 {
t.Fatal("Unexpected object info value for Size", objInfo.Size)
}
if objInfo.ModTime != timeSentinel {
t.Fatal("Unexpected object info value for ModTime ", objInfo.ModTime)
}
if objInfo.IsDir {
t.Fatal("Unexpected object info value for IsDir", objInfo.IsDir)
}
if !objInfo.Expires.IsZero() {
t.Fatal("Unexpected object info value for Expires ", objInfo.Expires)
}
}
// test whether a drive being offline causes
// getCachedLoc to fetch next online drive
func TestGetCachedLoc(t *testing.T) {
for n := 1; n < 10; n++ {
fsDirs, err := getRandomDisks(n)
if err != nil {
t.Fatal(err)
}
d, err := initDiskCaches(fsDirs, 100, 1, 80, 90, t)
if err != nil {
t.Fatal(err)
}
c := cacheObjects{cache: d}
bucketName := "testbucket"
objectName := "testobject"
// find cache drive where object would be hashed
index := c.hashIndex(bucketName, objectName)
// turn off drive by setting online status to false
c.cache[index].online = false
cfs, err := c.getCacheLoc(bucketName, objectName)
if n == 1 && err == errDiskNotFound {
continue
}
if err != nil {
t.Fatal(err)
}
i := -1
for j, f := range c.cache {
if f == cfs {
i = j
break
}
}
if i != (index+1)%n {
t.Fatalf("expected next cache location to be picked")
}
}
}
// test whether a drive being offline causes
// getCachedLoc to fetch next online drive
func TestGetCacheMaxUse(t *testing.T) {
for n := 1; n < 10; n++ {
fsDirs, err := getRandomDisks(n)
if err != nil {
t.Fatal(err)
}
d, err := initDiskCaches(fsDirs, 80, 1, 80, 90, t)
if err != nil {
t.Fatal(err)
}
c := cacheObjects{cache: d}
bucketName := "testbucket"
objectName := "testobject"
// find cache drive where object would be hashed
index := c.hashIndex(bucketName, objectName)
// turn off drive by setting online status to false
c.cache[index].online = false
cb, err := c.getCacheLoc(bucketName, objectName)
if n == 1 && err == errDiskNotFound {
continue
}
if err != nil {
t.Fatal(err)
}
i := -1
for j, f := range d {
if f == cb {
i = j
break
}
}
if i != (index+1)%n {
t.Fatalf("expected next cache location to be picked")
}
}
}
// test wildcard patterns for excluding entries from cache
func TestCacheExclusion(t *testing.T) {
cobjects := &cacheObjects{
cache: nil,
}
testCases := []struct {
bucketName string
objectName string
excludePattern string
expectedResult bool
}{
{"testbucket", "testobjectmatch", "testbucket/testobj*", true},
{"testbucket", "testobjectnomatch", "testbucet/testobject*", false},
{"testbucket", "testobject/pref1/obj1", "*/*", true},
{"testbucket", "testobject/pref1/obj1", "*/pref1/*", true},
{"testbucket", "testobject/pref1/obj1", "testobject/*", false},
{"photos", "image1.jpg", "*.jpg", true},
{"photos", "europe/paris/seine.jpg", "seine.jpg", false},
{"photos", "europe/paris/seine.jpg", "*/seine.jpg", true},
{"phil", "z/likes/coffee", "*/likes/*", true},
{"failbucket", "no/slash/prefixes", "/failbucket/no/", false},
{"failbucket", "no/slash/prefixes", "/failbucket/no/*", false},
}
for i, testCase := range testCases {
cobjects.exclude = []string{testCase.excludePattern}
if cobjects.isCacheExclude(testCase.bucketName, testCase.objectName) != testCase.expectedResult {
t.Fatal("Cache exclusion test failed for case ", i)
}
}
}
// Test diskCache.
func TestDiskCache(t *testing.T) {
fsDirs, err := getRandomDisks(1)
if err != nil {
t.Fatal(err)
}
d, err := initDiskCaches(fsDirs, 100, 0, 80, 90, t)
if err != nil {
t.Fatal(err)
}
c := cacheObjects{cache: d}
cache := c.cache[0]
ctx := context.Background()
bucketName := "testbucket"
objectName := "testobject"
content := "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
etag := "061208c10af71a30c6dcd6cf5d89f0fe"
contentType := "application/zip"
size := len(content)
httpMeta := make(map[string]string)
httpMeta["etag"] = etag
httpMeta["content-type"] = contentType
objInfo := ObjectInfo{}
objInfo.Bucket = bucketName
objInfo.Name = objectName
objInfo.Size = int64(size)
objInfo.ContentType = contentType
objInfo.ETag = etag
objInfo.UserDefined = httpMeta
var opts ObjectOptions
byteReader := bytes.NewReader([]byte(content))
hashReader, err := hash.NewReader(byteReader, int64(size), "", "", int64(size), globalCLIContext.StrictS3Compat)
if err != nil {
t.Fatal(err)
}
err = cache.Put(ctx, bucketName, objectName, hashReader, hashReader.Size(), nil, ObjectOptions{UserDefined: httpMeta}, false)
if err != nil {
t.Fatal(err)
}
cReader, _, err := cache.Get(ctx, bucketName, objectName, nil, http.Header{
"Content-Type": []string{"application/json"},
}, opts)
if err != nil {
t.Fatal(err)
}
cachedObjInfo := cReader.ObjInfo
if !cache.Exists(ctx, bucketName, objectName) {
t.Fatal("Expected object to exist on cache")
}
if cachedObjInfo.ETag != objInfo.ETag {
t.Fatal("Expected ETag to match")
}
if cachedObjInfo.Size != objInfo.Size {
t.Fatal("Size mismatch")
}
if cachedObjInfo.ContentType != objInfo.ContentType {
t.Fatal("Cached content-type does not match")
}
writer := bytes.NewBuffer(nil)
_, err = io.Copy(writer, cReader)
if err != nil {
t.Fatal(err)
}
if ccontent := writer.Bytes(); !bytes.Equal([]byte(content), ccontent) {
t.Errorf("wrong cached file content")
}
cReader.Close()
cache.Delete(ctx, bucketName, objectName)
online := cache.IsOnline()
if !online {
t.Errorf("expected cache drive to be online")
}
}
// Test diskCache with upper bound on max cache use.
func TestDiskCacheMaxUse(t *testing.T) {
fsDirs, err := getRandomDisks(1)
if err != nil {
t.Fatal(err)
}
d, err := initDiskCaches(fsDirs, 80, 0, 80, 90, t)
if err != nil {
t.Fatal(err)
}
cache := d[0]
ctx := context.Background()
bucketName := "testbucket"
objectName := "testobject"
content := "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
etag := "061208c10af71a30c6dcd6cf5d89f0fe"
contentType := "application/zip"
size := len(content)
httpMeta := make(map[string]string)
httpMeta["etag"] = etag
httpMeta["content-type"] = contentType
objInfo := ObjectInfo{}
objInfo.Bucket = bucketName
objInfo.Name = objectName
objInfo.Size = int64(size)
objInfo.ContentType = contentType
objInfo.ETag = etag
objInfo.UserDefined = httpMeta
opts := ObjectOptions{}
byteReader := bytes.NewReader([]byte(content))
hashReader, err := hash.NewReader(byteReader, int64(size), "", "", int64(size), globalCLIContext.StrictS3Compat)
if err != nil {
t.Fatal(err)
}
if !cache.diskAvailable(int64(size)) {
err = cache.Put(ctx, bucketName, objectName, hashReader, hashReader.Size(), nil, ObjectOptions{UserDefined: httpMeta}, false)
if err != errDiskFull {
t.Fatal("Cache max-use limit violated.")
}
} else {
err = cache.Put(ctx, bucketName, objectName, hashReader, hashReader.Size(), nil, ObjectOptions{UserDefined: httpMeta}, false)
if err != nil {
t.Fatal(err)
}
cReader, _, err := cache.Get(ctx, bucketName, objectName, nil, nil, opts)
if err != nil {
t.Fatal(err)
}
cachedObjInfo := cReader.ObjInfo
if !cache.Exists(ctx, bucketName, objectName) {
t.Fatal("Expected object to exist on cache")
}
if cachedObjInfo.ETag != objInfo.ETag {
t.Fatal("Expected ETag to match")
}
if cachedObjInfo.Size != objInfo.Size {
t.Fatal("Size mismatch")
}
if cachedObjInfo.ContentType != objInfo.ContentType {
t.Fatal("Cached content-type does not match")
}
writer := bytes.NewBuffer(nil)
_, err = io.Copy(writer, cReader)
if err != nil {
t.Fatal(err)
}
if ccontent := writer.Bytes(); !bytes.Equal([]byte(content), ccontent) {
t.Errorf("wrong cached file content")
}
cReader.Close()
cache.Delete(ctx, bucketName, objectName)
online := cache.IsOnline()
if !online {
t.Errorf("expected cache drive to be online")
}
}
}