If you have traditional spinning (hdd) drives, some applications with high concurrency might require MinIO cluster to be tuned such that to avoid random I/O on the drives. The way to convert high concurrent I/O into a sequential I/O is by reducing the number of concurrent operations allowed per cluster. This allows MinIO cluster to be operationally resilient to such workloads, while also making sure the drives are at optimal efficiency and responsive.

    heal legacy objects when versioning is enabled after upgrade (#13671)
```

- A security fix must be backported if a customer is affected by it, we have a mechanism in SUBNET to send out notifications to affected customers in such situations, this is a mandatory requirement.

```
commit 99bf4d0c429f04dbd013ba98840d07b759ae1702 (tag: RELEASE.2019-06-15T23-07-18Z)
Author: Harshavardhana <******@****.***>
Date:   Sat Jun 15 11:27:17 2019 -0700

package cmd

import (
	"syscall"
)

// Returns true if no error and there is no object or prefix inside this directory
func isDirEmpty(dirname string, legacy bool) bool {
	if legacy {
		// On filesystems such as btrfs, nfs this is not true, so fallback
		// to performing readdir() instead.
		entries, err := readDirN(dirname, 1)
		if err != nil {
			return false
		}
		return len(entries) == 0
	}
	var stat syscall.Stat_t

		}
	}

	return &LockedFile{File: f}, nil
}

// TryLockedOpenFile - tries a new write lock, functionality
// it is similar to LockedOpenFile with with syscall.LOCK_EX
// mode but along with syscall.LOCK_NB such that the function
// doesn't wait forever but instead returns if it cannot
// acquire a write lock.
func TryLockedOpenFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {

```
KEY:
api  manage global HTTP API call specific features, such as throttling, authentication types, etc.

ARGS:

	// that clients cannot decode the token using the temp
	// secret keys and generate an entirely new claim by essentially
	// hijacking the policies. We need to make sure that this is
	// based on admin credential such that token cannot be decoded
	// on the client side and is treated like an opaque value.
	claims, err := auth.ExtractClaims(token, secret)
	if err != nil {

	info.Major = unix.Major(devID)
	info.Minor = unix.Minor(devID)

	// Check for overflows.
	// https://github.com/minio/minio/issues/8035
	// XFS can show wrong values at times error out
	// in such scenarios.
	if info.Free > info.Total {
		return info, fmt.Errorf("detected free space (%d) > total drive space (%d), fs corruption at (%s). please run 'fsck'", info.Free, info.Total, path)
	}
	info.Used = info.Total - info.Free

	}
	var crossMounts mountInfos
	for _, mount := range mts {
		// Add a separator to indicate that this is a proper mount-point.
		// This is to avoid a situation where prefix is '/tmp/fsmount'
		// and mount path is /tmp/fs. In such a scenario we need to check for
		// `/tmp/fs/` to be a common prefix amount other mounts.
		mpath := strings.TrimSuffix(mount.Path, "/") + "/"
		ppath := strings.TrimSuffix(path, "/") + "/"
		if strings.HasPrefix(mpath, ppath) {

		return jwtgo.NewValidationError("accessKey/sub missing",
			jwtgo.ValidationErrorClaimsInvalid)
	}

	// Signature is valid, lets validate the claims for
	// other fields such as expiry etc.
	return claims.Valid()
}

// ParseUnverifiedStandardClaims - WARNING: Don't use this method unless you know what you're doing
//

			// whether you also have the s3:ListBucket
			// permission.
			// * If you have the s3:ListBucket permission
			//   on the bucket, Amazon S3 will return an
			//   HTTP status code 404 ("no such key")
			//   error.
			// * if you don’t have the s3:ListBucket
			//   permission, Amazon S3 will return an HTTP
			//   status code 403 ("access denied") error.`
			if globalPolicySys.IsAllowed(policy.BucketPolicyArgs{