269
72%

Ran 14 Nov 2018 03:13PM UTC

Jobs 1

Files 463

Run time 30s

Badge

Embed ▾

pending completion

Build # 269

Build Type

push

jenkins

Committed by GitHub

Commit Message

Added module to enable CPU affinity

### Motivation

This is part of a set of changes aimed at reducing latency in BK at the expense of other aspects (eg: max throughput). While not intended to be used as default settings, they might be good to have whenever the latency becomes critical. 

Pinning a thread to a particular CPU will ensure no other process will execute on that CPU reducing all scheduler induced context switches that will cause latency jittery.

A given thread that wants to get pinned to a CPU just needs to call: 

```java
CpuAffinity.acquireCore();
```

It's called `acquireCore()` because it will also disable hyper-threading on the pinned cpu.

Subsequent PRs will use this module to have the option to pin critical threads to available CPUs.

### Changes
 * Added JNI module to call `sched_setaffinity()` to pin a thread to a particular CPU
 * Automatically discover available isolated CPUs
 * Acquire file-based locks to allow multiple processes on same machine to acquire CPUs independently.

Reviewers: Ivan Kelly <ivank@apache.org>, Enrico Olivelli <eolivelli@gmail.com>, Sijie Guo <sijie@apache.org>

This closes #1641 from merlimat/cpu-affinity

Run Details

25300 of 35190 relevant lines covered (71.9%)

0.72 hits per line

Jobs

ID	Job ID	Ran	Files	Coverage
1	269.1	14 Nov 2018 03:13PM UTC	0	71.9

Source Files on build 269

Detailed source file information is not available for this build.

apache / bookkeeper / 269
72%

README BADGES
x

Markdown

Textile

RDoc

HTML

Rst

Jobs

Source Files on build 269

apache / bookkeeper / 269 72%

README BADGES x

Markdown

Textile

RDoc

HTML

Rst

Jobs

Source Files on build 269

apache / bookkeeper / 269
72%

README BADGES
x