Michael B. Greenwald. Non-blocking synchronization and system design. PhD thesis, Stanford University, 1999.  Home/Search   Document Details and Download   Summary   Related Articles   Check

.... and the real time NHRT follows research in recent years, in which several researchers have investigated the use of wait free shared object algorithms as an alternative to lock based mechanisms in object based real time systems [1, 2, 3, 7, 15, 17] Moreover, research in real time operating systems [6, 11, 9, 19] has also shown how to incorporate wait free techniques in real time kernels. Wait free implementation of shared data objects is an alternative approach for the problem of inter task communication and synchronization. Wait free mechanisms allow multiple tasks to access a shared object at the same ....

M. Greenwald. Non-Blocking Synchronization and System Design. PhD thesis, Stanford University, 1999.

....ed values and, if they all match, updates the locations with a further set of values. All this is performed atomically with respect to other CASN operations and specialized reads. The implementation of a non blocking multi word compare and swap operation has been the focus of many research papers [7, 10, 2, 3, 15, 5]. As we will show none of these provides a solution that is practicable in terms of the operations it requires from the processor, its storage costs and the features it supplies. This paper presents a new design that solves these problems. The solution is valuable because it nally allows many ....

....in terms of the operations it requires from the processor, its storage costs and the features it supplies. This paper presents a new design that solves these problems. The solution is valuable because it nally allows many algorithms requiring CASN to be used in earnest (for example those from [11, 5, 4]) CASN is useful as a foundation for building concurrent data structures because it can update a set of locations between consistent states. Aside from its applicability, our solution is notable in that it considers the full implementation path of the algorithm. Previous work has often needed a ....

[Article contains additional citation context not shown here]

M. Greenwald. Non-blocking synchronization and system design. PhD thesis, Stanford University, Aug. 1999.

.... As mentioned earlier, Lamport demonstrated that, in a sequentially consistent memory, atomic reads and writes can be implemented from non atomic reads and writes without mutual exclusion [94, 100, 101] Since then, extensive research has been conducted in lock free and wait free synchronization [8, 11, 17, 58, 63, 64, 65, 66, 75, 78, 119, 126, 127, 128, 138, 149, 158, 164]. Lock free and wait free operation implementations consist of code that typically executes multiple atomic statements and does not involve mutual exclusion. The correctness conditions for lock free and wait free implementations are necessarily more complicated than for mutual exclusion based ....

....hand, all lock free and wait free techniques are, by definition, non blocking. The most effective use of non blocking synchronization has been in the area of data structure specific algorithms. Greenwald provides an extensive discussion of non blocking synchronization techniques in his thesis [58]. 2.2.3.2 Limitations of lock free and wait free techniques Lock free and wait free techniques often require more complex operations than critical sections and rely on programmers to write appropriate code. Programmers have to reason about correctness in the presence of complex data structures. ....

Michael Greenwald. Non-blocking Synchronization and System Design. PhD thesis, Stanford University, Stanford, CA, 1999.

....with widths up to 8 bytes, stacks, and FIFO queues [Tre86, MS96] Valois introduced a lock free singly linked list design supporting insertions and deletions anywhere in a list, as well as several other data structures [Val95a, Val95b] These designs also work with just CAS. However, Greenwald [Gre99] has criticized them for being quite complex, difficult to get right, and computationally expensive. Most of the algorithms for lock free data structure synchronization that have been developed recently assume availability of a stronger atomic primitive like CAS2. These data structures include ....

....difficult to get right, and computationally expensive. Most of the algorithms for lock free data structure synchronization that have been developed recently assume availability of a stronger atomic primitive like CAS2. These data structures include general singly linked and doubly linked lists [Gre99] A number of techniques exist for implementing lock free and wait free MWCAS on top of CAS and CAS2, enabling nonblocking synchronization for arbitrarily complex data structures [Her93, Moi97, ARJ97a, Gre99] These techniques have considerable overhead in both space and runtime complexity, ....

[Article contains additional citation context not shown here]

Michael Greenwald. Non-blocking Synchronization and System Design. PhD thesis, Stanford University, August 1999.

....and deletion operations. The new algorithm provides substantial bene ts over previous schemes: it is conceptually simpler and our prototype operates substantially faster. 1 Introduction It is becoming evident that non blocking algorithms can deliver signi cant bene ts to parallel systems [MP91,LaM94,GC96,ABP98,Gre99]. Such algorithms use low level atomic primitives such as compare and swap through careful design and by eschewing the use of locks it is possible to build systems which scale to highly parallel environments and which are resilient to scheduling decisions. Linked lists are one of the most basic ....

.... comparison in this paper [MS95,Val01] To overcome the complexity of building linearizable lock free linked lists using CAS, Greenwald suggested a stronger double compare and swap (DCAS) primitive that atomically updates two storage locations after con rming that they both contain required values [Gre99]. DCAS is not available on today s multi processor architectures. However, it does admit a simple linearizable linkedlist algorithm: insertions proceed as described in Sect. 2 and deletions by atomic updates to the next eld of the cell being removed as well as that of its predecessor. ....

M Greenwald. Non-blocking synchronization and system design. PhD thesis, Stanford University, August 1999. Technical report STAN-CS-TR-99-1624.

...., it requires only one DCAS per push and one DCAS per pop. We also sketch a proof of correctness. 1 Introduction In academic circles and in industry, it is becoming evident that non blocking algorithms can deliver significant performance benefits [3, 20, 17] and resiliency benefits [9] to parallel systems. Unfortunately, there is a growing realization that existing synchronization operations on single memory locations, such as compare and swap (CAS) are not expressive enough to support design of efficient non blocking algorithms [9, 10, 12] and software emulations of stronger ....

....benefits [3, 20, 17] and resiliency benefits [9] to parallel systems. Unfortunately, there is a growing realization that existing synchronization operations on single memory locations, such as compare and swap (CAS) are not expressive enough to support design of efficient non blocking algorithms [9, 10, 12], and software emulations of stronger primitives from weaker ones are still too complex to be considered practical [1, 4, 7, 8, 21] In response, industry is currently examining the idea of supporting Array Array Linked Snark with used as list with (with centralized circular tagged garbage ....

[Article contains additional citation context not shown here]

M. Greenwald. Non-Blocking Synchronization and System Design. PhD thesis, Stanford University Technical Report STAN-CS-TR-99-1624, Palo Alto, CA, 1999.

....memory allocation mechanisms. In contrast, lock free implementations of dynamic data structures often either require maintenance of a special freelist , whose storage cannot in general be reused for other purposes (e.g. 19, 13] or require special system support such as type stable memory [6]. Our methodology is based on the well known 1 We do not specify how objects are created and destroyed; usually malloc and free are not lock free, so implementations based on them are also not lock free. However, most production quality malloc free implementations do attempt to avoid contention ....

....nodes explicitly in a freelist, thereby preventing the space consumption of a list from shrinking over time. Therefore, LFRCLoad uses DCAS to attempt to atomically increment the reference count, while ensuring that the pointer to the object still exists. A similar trick was used by Greenwald [6] in his universal constructions. This is achieved as follows. First, LFRCLoad reads the contents of A (line 4) If it sees a null pointer, there is no reference count to be incremented, so LFRCLoad simply sets dest to null (lines 5. 7) Otherwise, it reads the current reference count of the ....

M. Greenwald. Non-Blocking Synchronization and System Design. PhD thesis, Stanford University Technical Report STAN-CS-TR-99-1624, Palo Alto, CA, August 1999.

....sequentialize the access. Furthermore locks have the problem that if the process with the lock is blocked (e.g. swapped out by the OS or dies) then all processes can become blocked. To avoid this problem many non blocking (or lock free) implementations of data structures have been suggested [1, 2, 9, 10, 17, 18, 24, 25]. As with the versions that use This work was supported in part by the National Science Foundation under grants CCR 9706572 and CCR 0085982. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made ....

.... there has been considerable work on non blocking (or lock free) data structures [10] which only require that some user s request will complete in a bounded number of steps (although any particular user can be delayed indefinitely) Examples of non blocking data structures work includes [1, 2, 9, 10, 11, 17, 18, 24, 25]. Most of these implementations still fully sequentialize access to the data structure. Moreover, they often require unbounded memory 9 , or the use of atomic operations on two or more words of memory (such as a double compare andswap or transactional memory [12, 20] Such operations are ....

M. Greenwald. Non-Blocking Synchronization and System Design. PhD thesis, Stanford University, Palo Alto, CA, 1999. Tech. report STAN-CS-TR-99-1624.

....unbounded memory deque implementation. It too allows uninterrupted concurrent access to both ends of the deque. 1 Introduction In academic circles and in industry, it is becoming evident that non blocking algorithms can deliver significant performance [3, 23, 20] and resiliency benefits [11] to parallel systems. Unfortunately, there is a growing realization that existing synchronization operations on single memory locations, such as compare and swap (CAS) are not expressive enough to support design of e#cient non blocking algorithms [11, 12, 16] and software emulations of stronger ....

....[3, 23, 20] and resiliency benefits [11] to parallel systems. Unfortunately, there is a growing realization that existing synchronization operations on single memory locations, such as compare and swap (CAS) are not expressive enough to support design of e#cient non blocking algorithms [11, 12, 16], and software emulations of stronger primitives from weaker ones are still too complex to be considered practical [1, 4, 7, 8, 24] In response, industry is currently examining the idea of supporting stronger synchronization operations in hardware. A leading candidate among such operations is ....

[Article contains additional citation context not shown here]

Greenwald, M. Non-Blocking Synchronization and System Design. PhD thesis, Stanford University Technical Report STAN-CS-TR-99-1624, Palo Alto, CA, 8 1999.

No context found.

Michael B. Greenwald. Non-blocking synchronization and system design. Technical Report STAN-CS-TR-99-1624, Stanford University, June 1999. Ph.D. Thesis.

No context found.

M. B. Greenwald. Non-blocking synchronization and system design. Technical Report STAN-CS-TR-99-1624, Stanford University, June 1999. Ph.D. Thesis.

No context found.

Michael B. Greenwald. Non-blocking synchronization and system design. PhD thesis, Stanford University, 1999.

No context found.

M. B. Greenwald. Non-blocking Synchronization and System Design. PhD thesis, Stanford University, August 1999.

No context found.

M. Greenwald, Non-blocking synchronization and system design, Ph.D. dissertation, Stanford University, Palo Alto, CA, 1999.

No context found.

M. Greenwald, "Non-blocking synchronization and system design", PhD thesis, Stanford University, Technical report STAN-CASN-TR-99-1624, August 1999.

No context found.

M. Greenwald. Non-Blocking Synchronization and System Design. Ph.D. thesis, Stanford University, Palo Alto, CA, 1999. Technical Report STAN-CS-TR-99-1624.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC