Non-blocking Writes

Participants

Project Goals

  (Truly) Non-blocking Writes!

ToDo List

TODO's from 12/13/12 meeting

Setup the key-value store benchmark (YCSB) to test NBW (file system path).
Fix the CPU scheduler bug that could potentially influence the performance degradation shown by some of the benchmarks.
Setup the consolidated benchmark using qemu on a Linux host. Two possible options here:
- Use NBW at the host level and virtualize guest machines without KVM to create memory pressure at the hyper-visor level.
- Use vanilla host and virtualize guest machines using KVM and let NBW work at the guest level.
- We plan to set the base comparison level by partitioning statically the physical memory among all the VMs to let fit in memory each working set without problems.
  1. Incrementally we increase the amount of VMs (i.e workloads) so they start competing for memory. We measure the improvements in execution times of NBW compared to the vanilla system.
  2. The result of the benchmark is a vector of execution times where each dimension is the execution time of each workload in the consolidated system. There should be one vector for vanilla and NBW respectively.
Depending on time and the results of the key-value benchmark as a file system benchmark, explore other file systems benchmarks as databases or Filebench (possible using MongoDB as back-end)
With very low priority, we could rerun the SPEC SFS benchmark to see if there is any improvement by the inclusion of the read-from-patches implementation.

Future ToDo's

Get times of changing from user to kernel mode, and the other way around.
Test the system changing queue depths with NCQ.
Explore creation of persistent patches.
Implement NFS support.

Meetings

01/08/15: Non-blocking write curves for paper
12/16/14: Handling of journaling modes; Responding to shepherd; Simulation of cache misses for partial page writes (Hector)
12/09/14: FAST'15 Review Comments (Audio lost)
11/25/14: Intro feedback and trace-replayed brainstorming
11/18/14: Writing Feedback/Task; Trace-replay updates
11/12/14: Writing / development schedule
11/04/14: Brainstorming: Concrete paper plan “fast durable file writes to persistent memory”
10/28/14: Brainstorming: fast durable file writes to persistent memory
10/21/14: Tracing and Persistent Memory direction
10/14/14: Next evaluation steps; tracing work; Project ideas (persistent memory)
10/07/14: Brainstorming next paper and projects
09/16/14: Module data; sqlite updates; other eval plans
09/12/14: New data / module / Eval/Writing plans
09/09/14: Eval/Writing plans
09/02/14: Kernel module discussion, Paper writing plans and new data with mobigen trace replay
08/26/14: Mobigen data (Facebook/Twitter) and plans for Mobigen replay
08/19/14: More updates on module, SQLite, Mobibench, Filebench
08/12/14: Updates on module, SQLite, Mobibench, Filebench
08/05/14: 4 Directions for motivation (module-based data), persistent-memory, trace analysis, new benchmarks
07/22/14: Byte addressable memory cache (new motivation); kernel module plans
07/15/14: Kernel module plans and new data collection
07/08/14: OSDI'14 rebuttal
07/01/14: Analyzing blktrace data; new I/O scheduling improvements; NCQ setup by Hector
06/24/14: Next steps: CPU nicing for kernel-threads issuing NBW + updating filebench graphs
06/10/14: Next steps: Limiting I/O queueing for non-blocking fetches and moving I/Os across priority queues when status changes to blocking
06/06/14: I/O Scheduler implementation update; next steps
05/27/14: I/O Scheduler Optimization — Initial thoughts on implementation
04/24/14: Paper story-line I
04/22/14: Evaluation story-line and discussion of experiments
04/17/14: Evaluation outline/goals
04/15/14: New SpecSFS data is promising
03/20/14: OSDI paper discussion
03/04/14: New data with lazy; HotStorage paper?
02/13/14: Potential workloads for file system
02/06/14: Sawtooth performance explained and next steps for experiments
01/28/14: SMP works! Kernel Preemption works! Explaining sawtooth performance;
01/23/14: Understanding performance data
01/21/14: Understanding performance data
01/14/14: First great set of Filebench data!, YCSB+LevelDB? ATC submission plans
12/11/13: Implementation updates, review of paper outline
12/04/13: Paper outline (First draft) and discuss of current bugs
11/27/13: Bugs fixed, discussion about implementing pdflush, fsync, and lazy, paper outline and writing tasks
11/20/13: Two bugs, 1 solution and storyline update
11/13/13: Brief update
11/06/13: Story-line draft / scheduled implementation / deadlock solved
10/30/13: Deadlock!
10/23/13: Updates
10/16/13: FS-specific metadata is cached via page cache using device mapping!
10/11/13: Two options to explore for FS metadata blocking (1) lazy page fetching and (2) work-queue based threaded page fetching
10/09/13: Sync metadata access seems to block NBW; discussion of next steps
09/25/13: Seems like non-blocking writes are blocking!
09/23/13: Results examination for lazy, planning for filebench runs
09/20/13: Results examination, development, and paper writing tasks
09/18/13: Inspection of NFS client kernel-code
09/16/13: Results for SPECSfs and Filebench, updates on NFS client
09/13/13: Updates on filebench (fileserver) and SPECSfs
09/11/13: New workload plan – jdbc,jdbm,gdbm(java), etc.
09/06/13: New evaluation plan
08/28/13: Next steps: SpecSFS anaysis, I/O scheduler, other FS benchmarks
08/21/13: Updates on SPECSfs behavior and controlling runtime
08/19/13: Updates/discussion on NFS client – does it block on write?
08/14/13: Implementation update for CPU scheduler and some initial direction of NFS implementation; Results update (Aldo)
08/09/13: NFS server - async config, many updates from Daniel on development - NetApp project
07/31/13: Memory ordering discussion + updates from Aldo
07/24/13: I/O prioritization v.s. Lazy file system implementation + discussion of next set of configurations to run
07/17/13: Review of current status (Aldo, Daniel, Luis) and thoughts on syscall tracing
07/10/13: Discussion with Luis about FAST paper and Filesystem oriented submission
07/03/13: Discussion with Luis on implementation/documentation next steps
04/29/13: FIO new data points to NCQ being effective – need to test with larger file size in FIO
04/23/13: NCQ results indicate fake-ncq – Aldo will confirm with more expts; New results with Lazy (10K max patches) are promising
04/18/13: Three directions next: reliability/reproducability of data, NCQ, and Jesus' scheduler completion and integration with Lazy
04/11/13: Two primary strengths of NBW not capitalized in current implementation
03/28/13: Strategy discussion
03/26/13: New data – higher queue depths not proportional to fraction of NBW requests (request merging the answer?) (as single-stepping)
03/21/13: Potential source of failure identified (as single-stepping)
03/19/13: Failure issues with dacapo
01/31/13: Initial set of results with new CPU scheduler; next steps fix cpu scheduler optimization for mmap faulting processes; correlating counters with performance; I/O scheduler optimization; memory corruption issue
01/17/13: Updates and status of CPU scheduler implementation from Jesus
01/15/13: Memory sensitivity and benchmarks for evaluation
12/13/12: Evaluation plan revision (Meeting summary) (No audio)
12/06/12: Updates from Daniel, reviewing remaining tasks for paper submission
11/28/12: Fixed state-assignment bug in CPU scheduler; Dealing with NCQ queue lengths; experiments review
11/21/12: Hunting NCQ hardware and getting NCQ data for NBW, plans for knowledge transfer to Daniel
11/14/12: Updates on validating I/O priority inversion issue and VFS implementation, benchmarking and evaluation plans for paper submission
10/31/12: I/O scheduler optimizations and handling device-level queues; svnserver benchmark has negligible WriteFaults
10/24/12: Updates on VFS implementation
10/17/12: Updates on benchmarks and Do we need an I/O priority scheduler for NBW processes?
10/09/12: More updates on scheduler and benchmarks
10/03/12: Scheduling issue performance degradation, benchmark updates
09/26/12: Scheduling fixes and new results, anomaly with batik and pmd which have severe degradation
09/13/12: Plan and action items when Luis is absent
09/05/12: New data motivates scheduling as the next step, updates on NBW overhead breakdown
08/23/12: Understanding new data and next steps with implementation and benchmarks
08/16/12: Update on new CPU scheduler (almost done!) and reviewing evaluation plan
08/07/12: Prioritizing next set of action items
08/02/12: New evaluation plan
07/26/12: Discussing remaining OSDI feedback
07/24/12: New results with NBW scheduling optimizations + Discussing OSDI feedback
07/17/12: NBW CPU scheduler with new state + plans for collecting results from Jesus
07/10/12: Results review and new CPU yielding implementation (for Jesus)
07/03/12: NSF proposal comments & CPU scheduling optimization
06/26/12: Results with multi-threaded apps lackluster; yield optimization and SMP implementations; big picture of I/O and CPU parallelism in NBW
06/21/12: Bug fixes, new results, Luis thesis chapter feedback
06/12/12: Scheduled fetch design and async fetch results
04/10/12: New directions
04/03/12: Perils of prefetching and plugging!
04/02/12: Paper structure, stories, and data analysis
03/27/12: Disassembly doesn't seem to help with big-patch-queue! – Alternate evaluation plan
03/20/12: Update from Jesus on new disassembly implementation (to replace single-stepping)
03/06/12: More data and more analysis
03/02/12: Alternate explanations for data
02/28/12: Analyzing initial detailed data from benchmarks
02/23/12: Understanding minor fault and patch creation latencies
02/21/12: Explaining the data III
02/07/12: Request and page pools and ideas for deferred memory allocation
01/31/12: Trying out reboot/power-down and tracing blktrace problems
01/24/12: Explaining the data II
01/17/12: Explaining the data I
01/10/12: Discussion of issues with implementation and initial data
12/13/11: Updates and plans for new experiments (PCIe flash, memory sizing, SMP)
12/06/11: Experiment updates; some FS performance analysis;
11/29/11: Issues uncovered during merging of anon and fs
11/22/11: NSF Proposal Discussion
11/15/11: Brainstorming ideas for debugging filesystem component
11/08/11: Page fault handling - Normal and NBW versions - details for the paper & Experiment updates
11/01/11: Status updates
10/18/11: Discussion of statistics for analyzing performance
10/11/11: More performance testing of anonymous version
10/04/11: Initial performance of anonymous – promising results
09/20/11: Can we make FAST?
09/13/11: Implementation progress
09/06/11: update from Jesus, FS implementation, initial writing plans
08/30/11: Implementing patch application in process context, workloads for non-blocking FS writes, Deferred/No async read,
08/16/11: Updates
08/02/11: War of the Titans II - Disassembly vs. page diff-merge (and some very good advice on research prototyping too!)
07/26/11: using page flags and page-level locking
07/19/11: setting up async reads and other updates
07/12/11: handling async read completions, handling write syscalls
06/07/11: 32 vs. 64 bit porting of memcheck.c – next steps: porting to 64 bit, random single-step checks, radix/range/redblack tree based patch implementation
05/31/11: More generic w/ generic_fault_handler; thoughts on consistency and syscall implementation
05/23/11: Updates on patch implementation
05/17/11: Single stepping v.s. disassembly for write size
05/10/11: Initial thoughts on handling syscalls
05/03/11: Initial kernel design
04/19/11: Addressing Hotstorage review comments
03/11/11: Result review and Paper writing plans.
03/09/11: (evening skype call) Review
03/09/11: Deconstructing results, motivation discussion, and changes to graph data
03/04/11: Hotstorage paper structure

Systems Research Laboratory

Table of Contents

Non-blocking Writes

Participants

Project Goals

ToDo List

TODO's from 12/13/12 meeting

Future ToDo's

Meetings