Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. Colleagues/Internet I love using [Linux performance tools]. But I also love solving issues quickly, and sometimes that means just asking colleagues or searching the Internet. Microbenchmark os::javaTimeMillis() on both systems.

Speed 126

Speed Java AWS Virtualization 126

Highly Scalable

SEPTEMBER 18, 2012

Historically, NoSQL paid a lot of attention to tradeoffs between consistency, fault-tolerance and performance to serve geographically distributed systems, low-latency or highly available applications. Read/Write latency. Read/Write requests are processes with a minimal latency. Data Placement. Read/Write scalability.

Database 213

Database Latency C++ Scalability 213

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. Colleagues/Internet I love using Linux performance tools. But I also love solving issues quickly, and sometimes that means just asking colleagues or searching the Internet. Microbenchmark os::javaTimeMillis() on both systems.

Speed 52

Speed Java AWS Virtualization 52

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. Colleagues/Internet I love using [Linux performance tools]. But I also love solving issues quickly, and sometimes that means just asking colleagues or searching the Internet. Microbenchmark os::javaTimeMillis() on both systems.

Speed 40

Speed Java AWS Virtualization 40

Highly Scalable

MAY 1, 2012

Statistical analysis and mining of huge multi-terabyte data sets is a common task nowadays, especially in the areas like web analytics and Internet advertising. This approach often leads to heavyweight high-latency analytical processes and poor applicability to realtime use cases. Case Study. Counters on each position are incremented.

Analytics 191

Analytics Traffic Big Data Efficiency 191

Smashing Magazine

JANUARY 11, 2021

Alternatively, you can also use: Addy Osmani’s Chrome UX Report Compare Tool , Speed Scorecard (also provides a revenue impact estimator), Real User Experience Test Comparison or SiteSpeed CI (based on synthetic testing). Estimated Input Latency tells us if we are hitting that threshold, and ideally, it should be below 50ms.

Performance 145

Performance Cache Media Metrics 145

Brendan Gregg

SEPTEMBER 5, 2017

Here's some output from my zfsdist tool, in bcc/BPF, which measures ZFS latency as a histogram on Linux: # zfsdist. Tracing ZFS operation latency. Hit Ctrl-C to end. ^C C operation = 'read' usecs : count distribution 0 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 4479 | *| 8 -> 15 : 1028 | | 16 -> 31 : 14 | | 32 -> 63 : 1 | | [.].

Virtualization 76

Virtualization AWS Engineering Hardware 76