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What's the difference between a word and byte?
...e unit for a CPU. If you want to set/clear single bits, you first need to fetch the corresponding byte from memory, mess with the bits and then write the byte back to memory.
The word by contrast is biggest chunk of bits with which a processor can do processing (like addition and subtraction) at a ...
What is stability in sorting algorithms and why is it important?
...orithms are stable by nature like Insertion sort, Merge Sort, Bubble Sort, etc. And some sorting algorithms are not, like Heap Sort, Quick Sort, etc.
Background: a "stable" sorting algorithm keeps the items with the same sorting key in order. Suppose we have a list of 5-letter words:
peach
straw...
Controlling fps with requestAnimationFrame?
...
That's it, all the logic is handled internally.
Demo
var ctx = c.getContext("2d"), pTime = 0, mTime = 0, x = 0;
ctx.font = "20px sans-serif";
// update canvas with some information and animation
var fps = new FpsCtrl(12, function(e) {
ctx.clearRect(0, 0, c.width, c.height);
ctx.fil...
AtomicInteger lazySet vs. set
... "lazySet" method to the Atomic classes
(AtomicInteger, AtomicReference, etc). This is a niche
method that is sometimes useful when fine-tuning code using
non-blocking data structures. The semantics are
that the write is guaranteed not to be re-ordered with any
previous write, but may be r...
Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?
... the indexer process uses too.
Scalability is where my knowledge is more sketchy - but it's easy enough to copy index files to multiple machines and run several searchd daemons. The general impression I get from others though is that it's pretty damn good under high load, so scaling it out across mu...
One SVN repository or many?
... = none # or read or write
auth-access = write
password-db = /var/svn/conf/passwd
authz-db = /var/svn/conf/authz
realm = Repos1 SVN Repository
File: /var/svn/conf/authz
[groups]
group_repos1_read = user1, user2
group_repos1_write = user3, user4
group_repos2_read = user1, user4
### Global Right f...
SQL Server Management Studio, how to get execution time down to milliseconds
...
Then you get a new tab which records the timings, IO data and rowcounts etc for (up to) the last 10 exections (plus averages!):
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Is a LINQ statement faster than a 'foreach' loop?
...cts generally is going to add some marginal overheads (multiple iterators, etc). It still has to do the loops, and has delegate invokes, and will generally have to do some extra dereferencing to get at captured variables etc. In most code this will be virtually undetectable, and more than afforded b...
Can't su to user jenkins after installing Jenkins
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as root, enter su - jenkins
Also, check in /etc/passwd that user jenkins is allowed to logon: there should be something like /bin/bash or /bin/sh, certainly not /bin/false at the end of the line.
Hint: You don't use su and sudo at the same time.
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What exactly are “spin-locks”?
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When you use regular locks (mutexes, critical sections etc), operating system puts your thread in the WAIT state and preempts it by scheduling other threads on the same core. This has a performance penalty if the wait time is really short, because your thread now has to wait for ...