from OO to Multicore SST
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from OO to Multicore SST. An overview of SST describing Checkpoint and Transactional Memory Support for ROCK
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The following ppt's full topic covers Operating System for BSc CS, BCA, MSc CS, MCA students..
1.Introduction
2.OS Structures
3.Process
4.Threads
5.CPU Scheduling
6.Process Synchronization
7.Dead Locks
8.Memory Management
9.Virtual Memory
10.File system Interface
11.File system implementation
12.Mass Storage System
13.IO Systems
14.Protection
15.Security
16.Distributed System Structure
17.Distributed File System
18.Distributed Co Ordination
19.Real Time System
20.Multimedia Systems
21.Linux
22.Windows
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3) Once the scan chains are fully loaded, the controller shifts to the burst phase, in which the true functional clocks are applied. The scan chains are still left in the shift mode while the scan data rotates through the scan chains for a few cycles. Then a single capture cycle is applied and the data is shifted out.
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The document discusses process synchronization and solutions to the critical section problem. It introduces the producer-consumer problem as an example that requires synchronization. The critical section problem aims to ensure that only one process at a time can be executing shared code or accessing shared data. Peterson's algorithm provides a solution for two processes using shared variables. Hardware synchronization methods like mutex locks and semaphores provide atomic primitives to synchronize processes. Semaphores use wait() and signal() operations to control access to shared resources without busy waiting.
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Operating System Engineering
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Performance and predictability (1)
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This document discusses various low-level performance optimizations related to branch prediction, memory access, storage, and conclusions. It explains that branches can cause stalls, caches help mitigate slow memory access, and sequential access patterns outperform random access. The key themes are optimizing for predictability over randomness and prioritizing principles over specific tools.
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11thingsabout11g 12659705398222 Phpapp01
The document discusses several new features and enhancements in Oracle Database 11g Release 1. Key points include:
1) Encrypted tablespaces allow full encryption of data while maintaining functionality like indexing and foreign keys.
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The document discusses new features in Oracle Database 11g Release 1. Key points include:
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676.v3
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2. Continuation tracking is added to identify the origin of continuations for debugging. A "plugin context" tracks the originating plugin to tag continuations.
3. std::chrono is proposed to replace custom time handling in ATS. It provides type-safe time durations and timepoints without loss of precision during conversions.
4. Other active projects include partial object caching, event loop improvements, plugin priorities, making assertions no-ops in
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from OO to Multicore SST
- 1. From Superscalar OO to Multicore SST Checkpoint and Transactional memory support for SST © dave+stratusdesign@gmail.com stratusdesign.squarespace.com
- 13. SST logic Wakeup Behind Thread DQ Full? DQ Empty for current & spec ckpt? L1 Miss Set ‘ S ’ bit in Cache Start Behind thread in wait mode to handle Defers Start Executing Main thread Speculatively ahead Behind Thread Runs Thru DQ for Active Checkpoint Done Ahead Thread • Normal Mode Behind Thread • Pause L1 Resolved Ahead Thread • Scout Mode Behind Thread • Pause High Level SW initiates a Memory Transaction Restore Checkpoint Tx Fail ‘ S ’ bit Detect Mem Order Violation Br Mispredict Exception WAIT Begin SST Episode Arch Checkpoint Active • Architectural Inactive • Speculative Instr has Data Dependencies? Execute Instr and Retire OO Enqueue DQ with Instr & All Resolved Opr Instr has no Data Dependencies? WAIT more data expected Speculation Successful Program Execution resumes were speculation finished
- 14. SST scheduling Program Order LDX addr1, %r1 ADD %r1, 0x04, %r2 STX %r2, addr2 SETHI 0x01, %r2 STX %r2, addr3 etc.. ; Ahead-Thread 1 LDX addr1, %r1 ; Load Miss on addr1, Defer and set R1 [ NT ]) To Defer Q ; Checkpoint Start Ahead-Thread, Behind-Thread Waits for data read 2 ADD %r1, 0x04, %r2 ; Source Operand has NT bit set Defer and set R2 [NT] To Defer Q 3 STX %r2, addr2 ; Source Operand has NT bit set Defer) To Defer Q 4 SETHI 0x01, %r2 ; Ahead Thread Executes Independently) 5 STX %r2, addr3 ; Ahead Thread Executes Independently & continues speculative execution of more program instructions ; Load Miss resolves start Behind-Thread 6 ADD %r1, 0x04, %r2 [NT=0,SNT=1] ; NT was reset at 4, set waw bit 7 STX %r2, addr3 SST Order LDX addr1, %r1 ADD %r1, 0x04, %r2 STX %r2, addr2 SETHI 0x01, %r2 STX %r2, addr3 etc.. Deferring data-dependent instructions prevents RAW – here %r2 was read at 3 but written before at 2 Saving operands in DQ prevents WAR as any valid data in register at that time is captured and saved for Behind-Thread to use later regardless of future writes by Ahead-Thread Registers with WAW bit not committed to Architectural state – here %r2 was written at 4 & 6 ;Deferred Queue LDX addr1, %r1 [ NT ] ADD %r1 [ NT ], 0x04, %r2 [ NT ] STX %r2 [ NT ] , addr2 WAW WAR RAW