Compensate for different server pool sizes (#14968)

When a server pool with a different number of sets is added they are 
not compensated when choosing a destination pool for new objects. 
This leads to the unbalanced placement of objects with smaller pools 
getting a bigger number of objects since we only compare the destination 
sets directly.

This change will compensate for differences in set sizes when choosing
the destination pool.

Different set sizes are already compensated by fewer disks.
This commit is contained in:
Klaus Post 2022-05-24 18:57:14 -07:00 committed by GitHub
parent 38caddffe7
commit 41cdb357bb
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23

View file

@ -270,11 +270,13 @@ func (z *erasureServerPools) getAvailablePoolIdx(ctx context.Context, bucket, ob
// getServerPoolsAvailableSpace will return the available space of each pool after storing the content.
// If there is not enough space the pool will return 0 bytes available.
// The size of each will be multiplied by the number of sets.
// Negative sizes are seen as 0 bytes.
func (z *erasureServerPools) getServerPoolsAvailableSpace(ctx context.Context, bucket, object string, size int64) serverPoolsAvailableSpace {
serverPools := make(serverPoolsAvailableSpace, len(z.serverPools))
storageInfos := make([][]*DiskInfo, len(z.serverPools))
nSets := make([]int, len(z.serverPools))
g := errgroup.WithNErrs(len(z.serverPools))
for index := range z.serverPools {
index := index
@ -282,9 +284,11 @@ func (z *erasureServerPools) getServerPoolsAvailableSpace(ctx context.Context, b
if z.IsSuspended(index) {
continue
}
pool := z.serverPools[index]
nSets[index] = pool.setCount
g.Go(func() error {
// Get the set where it would be placed.
storageInfos[index] = getDiskInfos(ctx, z.serverPools[index].getHashedSet(object).getDisks())
storageInfos[index] = getDiskInfos(ctx, pool.getHashedSet(object).getDisks())
return nil
}, index)
}
@ -304,6 +308,14 @@ func (z *erasureServerPools) getServerPoolsAvailableSpace(ctx context.Context, b
}
available += disk.Total - disk.Used
}
// Since we are comparing pools that may have a different number of sets
// we multiply by the number of sets in the pool.
// This will compensate for differences in set sizes
// when choosing destination pool.
// Different set sizes are already compensated by less disks.
available *= uint64(nSets[i])
serverPools[i] = poolAvailableSpace{
Index: i,
Available: available,