Brendan Gregg

OCTOBER 7, 2018

Screenshot: tracing read latency for PID 181: # bpftrace -e 'kprobe:vfs_read /pid == 30153/ { @start[tid] = nsecs; } kretprobe:vfs_read /@start[tid]/ { @ns = hist(nsecs - @start[tid]); delete(@start[tid]); }'. Here's key differences as of August 2018: Type DTrace bpftrace. It's shaping up to be a DTrace version 2.0:

C++ 40

C++ Virtualization Programming Latency 40

KeyCDN

OCTOBER 24, 2018

Although both countries are relatively close to one another, they are separated by a distance of approximately 500km, which adds up in terms of latency. As of August 2018, Helsinki alone had a population of almost 650,000 people. As for Finland, it covers an area of over 338,000 square kilometers and has a population of over 5.5

Internet 48

Internet Internet Speed Network 48

HammerDB

MAY 5, 2019

However in the Skylake microarchitecture (you can see a list of CPUs here ) the PAUSE instruction changed and in the documentation it says “the latency of the PAUSE instruction in prior generation microarchitectures is about 10 cycles, whereas in Skylake microarchitecture it has been extended to as many as 140 cycles.”

Testing 49

Testing Tuning Storage Latency 49

HammerDB

OCTOBER 12, 2018

tpcc | DELIVERY | PROCEDURE | @ | 2018-10-11 08:57:34 | 2018-10-11 08:57:34 | DEFINER | | latin1 | latin1_swedish_ci | latin1_swedish_ci |. maximum transition latency: Cannot determine or is not supported. . c_ytd_payment: 10.00 7 rows in set (0.00 7 rows in set (0.00

Best Practices 40

Best Practices Scalability Performance C++ 40

HammerDB

NOVEMBER 5, 2018

Additionally for the log disk component it is latency for an individual write that is crucial rather than the total I/O bandwidth. A good example of how tuning is an iterative process. log 2018-11-02T15:39:25.628040+00:00 Thread 1 cannot allocate new log, sequence 1403. Checkpoint not complete. Checkpoint not complete.

Benchmarking 40

Benchmarking Database C++ Virtualization 40

Smashing Magazine

SEPTEMBER 6, 2021

Finally, not inlining resources has an added latency cost because the file needs to be requested. As such, a micro-optimization is, again, how you probably need to fine-tune things on a low level to really benefit from it. QUIPS , EPIQ 2018 , and EPIQ 2020. What Does It All Mean? Clients and QUIC Discovery.

Network 120

Network Servers Cache Traffic 120

Percona

AUGUST 10, 2018

This may help tune your table level autovacuum settings appropriately. sec < 2018-08-06 07:22:35.199 EDT > LOG: automatic analyze of table "vactest.scott.employee" system usage: CPU 0.00s/0.02u sec elapsed 0.15 Tuning Autovacuum in PostgreSQL. How do we identify the tables that need their autovacuum settings tuned ? .

Tuning 69

Tuning Cache Database Storage 69

John McCalpin

JANUARY 22, 2018

Dr. Damon McDougall gave a short presentation on this study at the IXPUG 2018 Fall Conference ( pdf ) — I originally wrote these notes to help organize my thoughts as we were preparing the IXPUG presentation, and later decided that the extra details contained here are interesting enough for me to post it.

Latency 40

Latency Hardware Code Testing 40

John McCalpin

JANUARY 22, 2018

Dr. Damon McDougall gave a short presentation on this study at the IXPUG 2018 Fall Conference ( pdf ) — I originally wrote these notes to help organize my thoughts as we were preparing the IXPUG presentation, and later decided that the extra details contained here are interesting enough for me to post it. cmpl $1000000000, %eax.

Latency 40

Latency Hardware Code Testing 40