Abstract: Systems and techniques for a memory-side cache directory-based request queue are described herein. A memory request is received at an interface of a memory device. One or more fields of the memory request are written into an entry of a directory data structure. The identifier of the entry is pushed onto a queue. To perform the memory request, the identifier is popped off of the queue and a field of the memory request is retrieved from the entry of the directory data structure using the identifier. Then, a process on the memory request can be performed using the field retrieved from the entry of the directory data structure.

Abstract: System and techniques for variable execution time atomic operations are described herein. When an atomic operation for a memory device is received, the run length of the operation is measured. If the run length is beyond a threshold, a cache line for the operation is locked while the operation runs. A result of the operation is queued until it can be written to the cache line. At that point, the cache line is unlocked.

Abstract: System and techniques for recall pending cache line eviction are described herein. A queue that includes a deferred memory request is kept for a cache line. Metadata for the queue is stored in a cache line tag. When a recall is needed, the metadata is written from the tag to a first recall storage, referenced by a memory request ID. After the recall request is transmitted, the memory request ID is written to a second recall storage referenced by the message ID of the recall request. Upon receipt of a response to the recall request, the queue for the cache line can be restored by using the message ID in the response to lookup the memory request ID from the second recall storage, then using the memory request ID to lookup the metadata from the first recall storage, and then writing the metadata into the tag for the cache line.

Abstract: System and techniques for host-preferred memory operation are described herein. At a memory-side cache of a memory device that includes accelerator hardware, a first memory operation can be received from a host. A determination that the first memory operation corresponds to a cache set based on an address of the first memory operation is made. A second memory operation can be received from the accelerator hardware. Another determination can be made that the second memory operation corresponds to the cache set. Here, the first memory operation can be enqueued in a host queue of the cache set and the second memory operation can be enqueued in an internal request queue of the cache set. The first memory operation and the second memory operation can be executed as each is dequeued.

Abstract: System and techniques for recall pending cache line eviction are described herein. A queue that includes a deferred memory request is kept for a cache line. Metadata for the queue is stored in a cache line tag. When a recall is needed, the metadata is written from the tag to a first recall storage, referenced by a memory request ID. After the recall request is transmitted, the memory request ID is written to a second recall storage referenced by the message ID of the recall request. Upon receipt of a response to the recall request, the queue for the cache line can be restored by using the message ID in the response to lookup the memory request ID from the second recall storage, then using the memory request ID to lookup the metadata from the first recall storage, and then writing the metadata into the tag for the cache line.

Abstract: System and techniques for variable execution time atomic operations are described herein. When an atomic operation for a memory device is received, the run length of the operation is measured. If the run length is beyond a threshold, a cache line for the operation is locked while the operation runs. A result of the operation is queued until it can be written to the cache line. At that point, the cache line is unlocked.

Abstract: System and techniques for evicting a cache line with pending control request are described herein. A memory request—that includes an address corresponding to a set of cache lines—can be received. A determination can be made that a cache line of the set of cache lines will be evicted to process the memory request. Another determination can be made that a control request has been made to a host from the memory device and that the control request pending when it is determined that the cache line will be evicted. Here, a counter corresponding to the set of cache lines can be incremented (e.g., by one) to track the pending control request in face of eviction. Then, the cache line can be evicted.

Abstract: System and techniques for memory side cache request handling are described herein. When a memory request is received, a cache set for the memory request is determined. Here, the cache set has multiple ways and each way corresponds to a cache line. It can be detected that a way of the multiple ways is not ready for the memory request. In this case, a representation of the memory request is stored in a queue of multiple queues based on an interface upon which the memory request was received and the present ways of the cache set. Entries from the multiple queues can be dequeued in a defined order to determine a next memory request to process. The defined order gives priority to memory requests for a present way and then for external over internal requests.

Abstract: System and techniques for synchronized request handling at a memory device are described herein. A request is received at the memory device. Here, the request indicates a memory address corresponding to a set of cache lines and a single cache line in the set of cache lines. The memory device maintains a deferred list for the set of cache lines and a set of lists with each member of the set of lists corresponding to one cache line in the set of cache lines. The memory device tests the deferred list to determine that the deferred list is not empty and places the request in the deferred list.

Abstract: System and techniques for silent cache line eviction are described herein. A memory device receives a memory operation from a host. The memory operation establishes data and metadata in a cache line of the memory device upon receipt. The metadata is stored in a memory element that corresponds to the cache line. Later, an eviction trigger to evict the cache line is identified. Then, in response to the eviction trigger, current metadata of the cache line is compared with the metadata in the memory element to determine whether the metadata has changed. the cache line can be evicted without writing to backing memory in response to the metadata being unchanged.

Abstract: Systems and techniques for a memory-side cache directory-based request queue are described herein. A memory request is received at an interface of a memory device. One or more fields of the memory request are written into an entry of a directory data structure. The identifier of the entry is pushed onto a queue. To perform the memory request, the identifier is popped off of the queue and a field of the memory request is retrieved from the entry of the directory data structure using the identifier. Then, a process on the memory request can be performed using the field retrieved from the entry of the directory data structure.

Abstract: System and techniques for memory side cache request handling are described herein. When a memory request is received, a cache set for the memory request is determined. Here, the cache set has multiple ways and each way corresponds to a cache line. It can be detected that a way of the multiple ways is not ready for the memory request. In this case, a representation of the memory request is stored in a queue of multiple queues based on an interface upon which the memory request was received and the present ways of the cache set. Entries from the multiple queues can be dequeued in a defined order to determine a next memory request to process. The defined order gives priority to memory requests for a present way and then for external over internal requests.

Abstract: A grass collection system may have an impeller with a through-shaft that mechanically couples power take off (PTO) energy to the mower deck. The PTO shaft may pass through the impeller and blower housing to power the mower deck, resulting in a compact mechanism. The PTO shaft may pass through a grass tunnel that connects between the blower housing and the mower deck, then may be connected to the mower deck to power the mower blades. The grass collection system may be deployed on a front mounted deck tractor that has front wheel drive. The front wheels may each have a hydrostatic pump and gearbox, and the PTO shaft may pass between or under the front wheel drive systems in connecting to the mower deck.

Abstract: A round mower deck for a rotary lawn mower may have a leading edge extension near the sides of the deck to improve cutting performance at the edge of a cutting swath. The leading edge extension may be mounted on an otherwise curved leading edge of a mower deck within the last few inches of the deck width. The leading edge extension may overlap some portion of the cutting stroke of a blade, and may prevent grass from being deflected away from the blade, resulting in a poor cut near the edge of a cutting swath. In some cases, the extension may be removable and may be added to an existing mower deck.

Abstract: A grass collection system may have an impeller with a through-shaft that mechanically couples power take off (PTO) energy to the mower deck. The PTO shaft may pass through the impeller and blower housing to power the mower deck, resulting in a compact mechanism. The PTO shaft may pass through a grass tunnel that connects between the blower housing and the mower deck, then may be connected to the mower deck to power the mower blades. The grass collection system may be deployed on a front mounted deck tractor that has front wheel drive. The front wheels may each have a hydrostatic pump and gearbox, and the PTO shaft may pass between or under the front wheel drive systems in connecting to the mower deck.

Abstract: A flexible coupler for rotary power transmission may have several rubber bushings oriented in a circle about a coupler axis. The bushings may join two flanged components to form a single coupler. A single coupler may be used in applications where the axes of two transmission shafts are not parallel. Two couplers may be joined by a transmission shaft for applications where the axes of two transmission shafts may be parallel but offset from each other.

Abstract: A flexible coupler for rotary power transmission may have several rubber bushings oriented in a circle about a coupler axis. The bushings may join two flanged components to form a single coupler. A single coupler may be used in applications where the axes of two transmission shafts are not parallel. Two couplers may be joined by a transmission shaft for applications where the axes of two transmission shafts may be parallel but offset from each other.

Abstract: A high-clearance dump system is described for use with a riding mower. A folding lift assembly lifts the catcher box up and away from the riding mower to allow dumping over and away from the walls of a truck or other receiving vehicle. The folding lift assembly interfolds into the dumping catcher assembly and the dump system mount assembly thus providing a low-profile when in the lowered position. A lift pivot arm, and lift control rods that are shorter than the lift pivot arm, cause the catcher frame to be tilted at an obtuse angle with respect to the lift pivot arm so that the back end of the catcher frame is higher than the front end of the catcher frame when the lift pivot arm is raised, thus providing high clearance. A power system provides power a switch box that switches power between a lift cylinder and a dump cylinder so that the catcher may be dumped in a raised, partially raised, or lowered position.

Abstract: Disclosed is a self propelled walk behind mower comprised of a tractor unit and a mowing deck. The tractor unit is hydrostatically driven with a unique control system whereby the forward speed of the tractor is set by operating an electric rocker switch with an operator's thumb. Hand levers are used to turn the tractor to the left and the right. The tractor unit comprises two drive wheels and a third wheel that is pivotally attached, letting the tractor unit stand upright when no implements are attached. Implements attach to the front of the tractor through a movable attachment so that the tractor and implement can closely follow the contour of the ground while keeping the operator controls in a convenient position.

Abstract: A self propelled walk behind mower including a tractor unit and a mowing deck. The tractor unit is hydrostatically driven with a unique control system whereby the forward speed of the tractor is set by operating an electric rocker switch with an operator's thumb. Hand levers are used to turn the tractor to the left and the right. The tractor unit comprises two drive wheels and a third wheel that is pivotally attached, letting the tractor unit stand upright when no implements are attached. Implements attach to the front of the tractor through a movable attachment so that the tractor and implement can closely follow the contour of the ground while keeping the operator controls in a convenient position.