CN102722446B

CN102722446B - Dynamic recorder for local memory access model for stream processor

Info

Publication number: CN102722446B
Application number: CN201210185144.XA
Authority: CN
Inventors: 史晓华
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2012-06-06
Filing date: 2012-06-06
Publication date: 2015-03-25
Anticipated expiration: 2032-06-06
Also published as: CN102722446A

Abstract

The invention relates to a dynamic recorder for a local memory access model for a stream processor, and belongs to the technical field of microprocessor system structure and compiling. The dynamic recorder comprises a local memory access switching module and an access record module. The local memory access switching module switches access to the local memory of all threads and records associated information therein in the other module i.e. the access record module. The access record module is a memory unit or a register unit provided with M fixed-length records. The dynamic recorder for the local memory access model for the stream processor provided by the invention has less impact on the operating efficiency of original programs, does not modify correction of the original programs, has no impact on semantic of the original programs, and can dynamically record the threads and program addresses which lead to maximum conflicts of local memory blocks.

Description

A kind of local memory access module dynamic recorder towards stream handle

Technical field

The present invention relates to a kind of local memory access module dynamic recorder towards stream handle, belong to micro-processor architecture and technique of compiling field.

Background technology

Stream handle is one of processor type of being used widely in computer systems, which at present, and it is represented as GPU, i.e. graphic process unit.Stream handle has outstanding odds for effectiveness in the Floating-point Computation of large-scale data, is therefore also used to high-performance calculation and parallel data processing.

Stream handle has significantly different from typical architecture such as CPU in memory Accessing Mechanism, after this makes many former programs of being converted into and stream handle running of designing program based on CPU, can meet with efficiency bottle neck on internal storage access, and wherein most representative efficiency bottle neck comes from the access conflict to local memory block in stream handle.The access module of local memory in stream handle when logging program runs, the access conflict of wherein local memory block can be located, after obtaining these related datas, programming personnel, compiler or stream handle itself, the optimization method of program pin to local internal storage access can be cooked up, thus improve the operational efficiency of program.

Summary of the invention

For problems of the prior art, the present invention proposes a kind of local memory access module dynamic recorder towards stream handle, solves and how to find and add up the problem that the program caused due to access local memory block conflict runs bottleneck.

The present invention proposes a kind of local memory access module dynamic recorder towards stream handle, and described dynamic recorder comprises local memory access interconnecting module and Visitor Logs module two parts.

The access of all threads to local memory is transferred by described local memory access interconnecting module, and relevant information is wherein recorded in another module and Visitor Logs module; Described Visitor Logs module is internal storage location or the register cell with M fixed-length record.The size of M depends on the ability of stream handle hardware or operating system software, the IA of the packets of information vinculum journey that each record comprises, accessed local memory block number, thread number and visiting frequency.

The control procedure that realizes of local memory access interconnecting module comprises following step:

Step one: when local memory access patterns dynamic recorder obtain the thread A IA P in the program of current operation to the access application of local memory block O after, enter step 2;

Step 2: judge whether address P is present in existing Visitor Logs module, if, by this record position in the thread number write-access logging modle of thread A, and the frequency in record is added 1, when in a certain record, L thread number is fully occupied, and thread number to be written all different from existing thread number time, can an optional current thread number cover, or abandon write; If not, perform step 3; The size of L depends on the ability of hardware or software.

Step 3: judge that whether the memory space of current accessed logging modle is full, if so, find the record that visiting frequency is minimum, deleted; If not, perform step 4;

According to the working mechanism of local memory access interconnecting module, when the memory space of all M all occupied i.e. Visitor Logs module of record is full, record minimum for visiting frequency in existing record can cover by new record to be written, ensures that the record that always visiting frequency is maximum is present in Visitor Logs module; If recording that visiting frequency is minimum is multiple, chooses arbitrarily one of them and cover.

Step 4: increase by 1 new Visitor Logs in Visitor Logs module, the information such as the IA of thread A, accessed local memory block number, current thread number are write this record, and frequency is set to 1;

Step 5: continue to perform current thread A to the access of local memory block O.

The invention has the advantages that:

(1) the present invention proposes a kind of local memory access module dynamic recorder towards stream handle, less on the operational efficiency impact of original program;

(2) the present invention proposes a kind of local memory access module dynamic recorder towards stream handle, does not do to change, do not affect the semanteme of original program to original program correctness;

(3) the present invention proposes a kind of local memory access module dynamic recorder towards stream handle, can the dynamically recording thread that causes the conflict of local memory block maximum and program address;

Accompanying drawing explanation

Fig. 1 is the structural representation of Visitor Logs device in the present invention;

Fig. 2 is the flow chart of local memory access interconnecting module in the present invention.

Detailed description of the invention

Below in conjunction with accompanying drawing, the present invention is described in further detail.

The present invention proposes a kind of local memory access module dynamic recorder towards stream handle, and its structure as shown in Figure 1, comprises local memory access interconnecting module and Visitor Logs module two parts:

Described local memory access interconnecting module as shown in Figure 1, the access of all threads to local memory is transferred by this module, and relevant information is wherein recorded in another module and Visitor Logs module, this module can be realized by programming language, such as C or C Plus Plus, also can realize in microprocessor chip." local memory block " in Fig. 1, refer to existing local memory block in stream handle, " thread " refers to the current thread run on stream handle.

The control procedure that realizes of local memory access interconnecting module comprises following step, as shown in Figure 2:

Step 2: judge whether address P is present in existing Visitor Logs module, if, by this record position in the thread number write-access logging modle of thread A, and the frequency in record is added 1, when in a certain record, L thread number is fully occupied, and thread number to be written all different from existing thread number time, can an optional current thread number cover, or abandon write; If not, perform step 3;

Described Visitor Logs module is internal storage location or a register cell with M fixed-length record, and the size of M depends on the ability of stream handle hardware or operating system software, such as, can be 16,256 or more.Wherein, the information that each record comprises comprises (but being not limited to): the information such as the IA of thread, accessed local memory block number, thread number and visiting frequency, wherein thread number can be multiple, as mostly being most L in Fig. 1, the size of L depends on the ability of hardware or software, such as, can be 4,16 or more.According to the working mechanism of local memory access interconnecting module, when in a certain record, L thread number is fully occupied, and when thread number to be written is all different from existing thread number, an optional current thread number can cover, or abandon write.

According to the working mechanism of local memory access interconnecting module, when the memory space of all M all occupied i.e. Visitor Logs module of record is full, record minimum for visiting frequency in existing record can cover by new record to be written, ensures that the record that always visiting frequency is maximum is present in Visitor Logs module.If recording that visiting frequency is minimum is multiple, chooses arbitrarily one of them and cover.

Claims

1. towards a local memory access module dynamic recorder for stream handle, it is characterized in that: described dynamic recorder comprises local memory access interconnecting module and Visitor Logs module two parts;

The access of all threads to local memory is transferred by described local memory access interconnecting module, and relevant information is wherein recorded in another module and Visitor Logs module; Described Visitor Logs module is internal storage location or the register cell with M fixed-length record; The size of M depends on the ability of stream handle hardware or operating system software, the IA of the packets of information vinculum journey that each record comprises, accessed local memory block number, thread number and visiting frequency;

Step one: when obtain the thread A IA P in present procedure to the access application of local memory block O after, enter step 2;

Step 2: judge whether address P is present in existing Visitor Logs module, if, by the record position in the thread number write-access logging modle of thread A, and the frequency in record is added 1, when in a certain record, L thread number is fully occupied, and thread number to be written all different from existing thread number time, can an optional current thread number cover, or abandon write; If not, perform step 3; The size of L depends on the ability of hardware or software;

According to the working mechanism of local memory access interconnecting module, when the memory space of all M all occupied i.e. Visitor Logs module of record is full, record minimum for visiting frequency in existing record can cover by new record to be written, ensures that the record that always visiting frequency is maximum is present in Visitor Logs module; If recording that visiting frequency is minimum is multiple, chooses arbitrarily one of them and cover;

Step 4: the Visitor Logs that increase by 1 is new in Visitor Logs module, the IA of thread A, accessed local memory block number, current thread information are write this record, and frequency is set to 1;