Struct BlockQueueStats

blockdevice/stats.go:95–180

BlockQueueStats models the queue files that are located in the sysfs tree for each block device and described in the kernel documentation: https://www.kernel.org/doc/Documentation/block/queue-sysfs.txt https://www.kernel.org/doc/html/latest/block/queue-sysfs.html

// https://www.kernel.org/doc/Documentation/block/queue-sysfs.txt
// https://www.kernel.org/doc/html/latest/block/queue-sysfs.html
type BlockQueueStats struct {
	// AddRandom is the status of a disk entropy (1 is on, 0 is off).
	AddRandom uint64
	// Dax indicates whether the device supports Direct Access (DAX) (1 is on, 0 is off).
	DAX uint64
	// DiscardGranularity is the size of internal allocation of the device in bytes, 0 means device
	// does not support the discard functionality.
	DiscardGranularity uint64
	// DiscardMaxHWBytes is the hardware maximum number of bytes that can be discarded in a single operation,
	// 0 means device does not support the discard functionality.
	DiscardMaxHWBytes uint64
	// DiscardMaxBytes is the software maximum number of bytes that can be discarded in a single operation.
	DiscardMaxBytes uint64
	// HWSectorSize is the sector size of the device, in bytes.
	HWSectorSize uint64
	// IOPoll indicates if polling is enabled (1 is on, 0 is off).
	IOPoll uint64
	// IOPollDelay indicates how polling will be performed, -1 for classic polling, 0 for hybrid polling,
	// with greater than 0 the kernel will put process issuing IO to sleep for this amount of time in
	// microseconds before entering classic polling.
	IOPollDelay int64
	// IOTimeout is the request timeout in milliseconds.
	IOTimeout uint64
	// IOStats indicates if iostats accounting is used for the disk (1 is on, 0 is off).
	IOStats uint64
	// LogicalBlockSize is the logical block size of the device, in bytes.
	LogicalBlockSize uint64
	// MaxHWSectorsKB is the maximum number of kilobytes supported in a single data transfer.
	MaxHWSectorsKB uint64
	// MaxIntegritySegments is the max limit of integrity segments as set by block layer which a hardware controller
	// can handle.
	MaxIntegritySegments uint64
	// MaxSectorsKB is the maximum number of kilobytes that the block layer will allow for a filesystem request.
	MaxSectorsKB uint64
	// MaxSegments is the number of segments on the device.
	MaxSegments uint64
	// MaxSegmentsSize is the maximum segment size of the device.
	MaxSegmentSize uint64
	// MinimumIOSize is the smallest preferred IO size reported by the device.
	MinimumIOSize uint64
	// NoMerges shows the lookup logic involved with IO merging requests in the block layer. 0 all merges are
	// enabled, 1 only simple one hit merges are tried, 2 no merge algorithms will be tried.
	NoMerges uint64
	// NRRequests is the number of how many requests may be allocated in the block layer for read or write requests.
	NRRequests uint64
	// OptimalIOSize is the optimal IO size reported by the device.
	OptimalIOSize uint64
	// PhysicalBlockSize is the physical block size of device, in bytes.
	PhysicalBlockSize uint64
	// ReadAHeadKB is the maximum number of kilobytes to read-ahead for filesystems on this block device.
	ReadAHeadKB uint64
	// Rotational indicates if the device is of rotational type or non-rotational type.
	Rotational uint64
	// RQAffinity indicates affinity policy of device, if 1 the block layer will migrate request completions to the
	// cpu “group” that originally submitted the request, if 2 forces the completion to run on the requesting cpu.
	RQAffinity uint64
	// SchedulerList contains list of available schedulers for this block device.
	SchedulerList []string