20318: Add config entry for keep-web cache size.

[arvados.git] / sdk / go / arvados / keep_cache.go

diff --git a/sdk/go/arvados/keep_cache.go b/sdk/go/arvados/keep_cache.go
index af80daa2e07647346fd628eda6b7acdbc2338295..a6571538761ef2411047c5ce97fd42122a93e6e6 100644 (file)
--- a/sdk/go/arvados/keep_cache.go
+++ b/sdk/go/arvados/keep_cache.go
@@ -37,7 +37,7 @@ type KeepGateway interface {
 type DiskCache struct {
        KeepGateway
        Dir     string
-       MaxSize int64
+       MaxSize ByteSizeOrPercent
        Logger  logrus.FieldLogger
 
        tidying        int32 // see tidy()
@@ -534,7 +534,7 @@ func (cache *DiskCache) gotidy() {
        // is below MaxSize, and we haven't reached the "recheck
        // anyway" time threshold.
        if cache.sizeMeasured > 0 &&
-               atomic.LoadInt64(&cache.sizeEstimated) < cache.MaxSize &&
+               atomic.LoadInt64(&cache.sizeEstimated) < atomic.LoadInt64(&cache.defaultMaxSize) &&
                time.Now().Before(cache.tidyHoldUntil) {
                atomic.AddInt32(&cache.tidying, -1)
                return
@@ -548,14 +548,26 @@ func (cache *DiskCache) gotidy() {
 
 // Delete cache files as needed to control disk usage.
 func (cache *DiskCache) tidy() {
-       maxsize := cache.MaxSize
+       maxsize := int64(cache.MaxSize.ByteSize())
        if maxsize < 1 {
-               if maxsize = atomic.LoadInt64(&cache.defaultMaxSize); maxsize == 0 {
+               maxsize = atomic.LoadInt64(&cache.defaultMaxSize)
+               if maxsize == 0 {
+                       // defaultMaxSize not yet computed. Use 10% of
+                       // filesystem capacity (or different
+                       // percentage if indicated by cache.MaxSize)
+                       pct := cache.MaxSize.Percent()
+                       if pct == 0 {
+                               pct = 10
+                       }
                        var stat unix.Statfs_t
                        if nil == unix.Statfs(cache.Dir, &stat) {
-                               maxsize = int64(stat.Bavail) * stat.Bsize / 10
+                               maxsize = int64(stat.Bavail) * stat.Bsize * pct / 100
+                               atomic.StoreInt64(&cache.defaultMaxSize, maxsize)
+                       } else {
+                               // In this case we will set
+                               // defaultMaxSize below after
+                               // measuring current usage.
                        }
-                       atomic.StoreInt64(&cache.defaultMaxSize, maxsize)
                }
        }
 
@@ -611,7 +623,8 @@ func (cache *DiskCache) tidy() {
 
        // If MaxSize wasn't specified and we failed to come up with a
        // defaultSize above, use the larger of {current cache size, 1
-       // GiB} as the defaultSize for subsequent tidy() operations.
+       // GiB} as the defaultMaxSize for subsequent tidy()
+       // operations.
        if maxsize == 0 {
                if totalsize < 1<<30 {
                        atomic.StoreInt64(&cache.defaultMaxSize, 1<<30)