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wallstprog

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Perfume reviews 1 year ago

A great book that has perfume as a major plot point is "Jitterbug Perfume" by Tom Robbins.

" I also managed to make contended nsync mutexes go 30% faster than nsync upstream on AARCH64, by porting it to use C11 atomics."

Curious about this -- so what does C11 atomics use to implement? At least in Linux, C++11 atomics use pthreads (not the other way around).

You might want to take a look at https://github.com/nyfix/memleaktest

We've open-sourced the tools we use to run valgrind (and ASAN) on large mixed C++/Java code bases. The JVM in particular triggers a slew of errors which can make filtering valgrind output impractical, but the scripts we developed can handle that. FWIW, we use these tools every day on the code that goes into NYFIX Marketplace (https://www.broadridge.com/financial-services/capital-market...).

I thought it was a brilliant design, but it was dog-slow on hardware at the time. I keep hoping someone would revive the design for current silicon, would be a good impedance match for modern languages, and OS's.

At my day job we run > 50 million messages per day through ZeroMQ, and have been quite pleased with its performance and stability (https://github.com/nyfix/OZ/tree/master#who-uses-it).

But the truth is that ZeroMQ has a steep learning curve, and some rather sharp edges that can leave nasty cuts if one is not careful.

If you're interested in becoming familiar with ZeroMQ, you might want to check out our implementation: <https://github.com/nyfix/OZ/>.

Well, the original non-thread-safe sockets (e.g., ZMQ_SUB, etc.) were that way because they support multi-part messages. And yes, the fact that they are not thread-safe is a bit of a stumbling-block for ZeroMQ newbies (including me, back in the day).

However, it's not that hard to work around their non-thread-safe nature with a single dispatch thread (e.g., see <https://github.com/nyfix/OZ/blob/master/src/transport.c#L457>), and that approach has other potential benefits.

In any case, newer socket types (e.g., ZMQ_CLIENT) have since been defined that are thread-safe, but necessarily don't support multi-part messages. (They tend to be different in other ways as well -- e.g., ZMQ_RADIO/ZMQ_DISH are "sort of" replacements for the original ZMQ_PUB/ZMQ_SUB sockets, but have other constraints as well).

Unlikely, but they seem to be different things altogether. BlazingMQ appears to be a traditional message queue (think ActiveMQ), with message peristence. ZeroMQ is more of a network middleware (think Tibco Rendezvous), and does not include persistence.

BlazingMQ also appears to be more of a "platform" or "service" that an app can use (sort of like Oracle, say) -- ZeroMQ includes libraries that one can use to build an app, service or platform, but none is provided "out of the box".

Which makes it harder to get started with ZeroMQ, since by definition every ZeroMQ app is essentially built "from scratch".

If you're interested in ZeroMQ, you may want to check out OZ (https://github.com/nyfix/OZ), which is a Rendezvous-like platform that uses the OpenMAMA API (https://github.com/finos/OpenMAMA) and ZeroMQ (https://github.com/zeromq/libzmq) transport to provide a full-featured network middleware implementation. OZ has been used in our shop since 2020 handling approx 50MM high-value messages per day on our global FIX network.

NYC Slice 4 years ago

There's not much that Staten Island has to brag about, but pizza is one of those things, and SI is very much under-represented here.

valgrind is great, but be aware that valgrind runs single-threaded, which definitely changes the way multi-threaded apps behave: https://valgrind.org/docs/manual/manual-core.html#manual-cor...

In practice what this means is that cpu-bound threads can monopolize the single thread, and we've had thread starvation issues as a result in some tests. Setting the "-fair-sched" option resolved those issues, but made valgrind run even slower ...

Back in the mid-70's Manufacturers Hanover Bank used to give candidates a "Programmer Aptitude Test", which was basically an IQ test. If you passed you were hired, and they paid to send you to a 12-week class that taught S/360 assembler & COBOL.

I took Comp Sci. in college, but my class also had math majors, actors, and all sorts of other people. IIRC it was about 50/50 men/women.

ACHTUNG! ALLES LOOKENSPEEPERS!

Das computermachine ist nicht fuer gefingerpoken und mitten grabben.

Ist easy schnappen der springen werk, blowenfusen und poppencorken mit spitzensparken.

Ist nicht fuer gewerken bei das dumpkopfen.

Das rubbernecken sichtseeren keepen das cotten-pickenen hans in das pockets muss; relaxen und watchen das blinkenlichten.

Another fan of Beyond Compare here, but I want to point out something everyone else has missed so far, which is that BC is great for comparing all sorts of files, not just code.

For example, I use its "Table Compare" feature to compare log files from different machines, sorted by timestamp. This lets me easily see the order of operations in a distributed system.