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How do I automatically update a timestamp in PostgreSQL
... Says so in the Postgres documentation of the types. Varchar has extra CPU cycles to check for the constraint, which doesn't happen on TEXT.
– Rahly
Jun 21 '17 at 15:50
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How to destroy an object?
...for "speed", but if you want to reclaim memory immediately (at the cost of CPU) should want to use null.
Like others mentioned, setting to null doesn't mean everything is reclaimed, you can have shared memory (uncloned) objects that will prevent destruction of the object. Moreover, like others h...
What is non-blocking or asynchronous I/O in Node.js?
...ng, asynchronous operations is that you can maximize the usage of a single CPU as well as memory.
Synchronous, blocking example
An example of synchronous, blocking operations is how some web servers like ones in Java or PHP handle IO or network requests. If your code reads from a file or the datab...
HTTP vs HTTPS performance
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The overhead is NOT due to the encryption. On a modern CPU, the encryption required by SSL is trivial.
The overhead is due to the SSL handshakes, which are lengthy and drastically increase the number of round-trips required for a HTTPS session over a HTTP one.
Measure (using a ...
How many parameters are too many? [closed]
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A good rule-of-thumb is the number of CPU registers, because anymore and the compiler will be forced to allocate them on the stack.
– Michaelangel007
Mar 31 '16 at 14:10
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Why prefer two's complement over sign-and-magnitude for signed numbers?
...h positive and negative numbers can all be done by the same circuit in the cpu.
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Encapsulation vs Abstraction?
...f you go down all the way to the raw silicon, the people who designed your CPU did so using circuit diagrams written in terms of "diodes" and "transistors", which are abstractions of how electrons travel through semiconductor crystals.
In software, everything is an abstraction. We build programs wh...
TCP loopback connection vs Unix Domain Socket performance
...x Domain Sockets (UDS), and PIPEs.
Here you have the results on a single CPU 3.3GHz Linux machine :
TCP average latency: 6 us
UDS average latency: 2 us
PIPE average latency: 2 us
TCP average throughput: 0.253702 million msg/s
UDS average throughput: 1.733874 million msg/s
PIPE average throug...
Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
...lation unit (for example: a foreign library, a file on disc, network data, CPU page tables, ...). In such a case the binary structure of data is also defined in a place inaccessible to the compiler, so reordering the struct fields would create a data type that is inconsistent with the other definiti...
App Inventor 2 SQLite 拓展：超流行兼容主流SQL语法的迷你本地数据库引擎 ...
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