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Microsecond timing in JavaScript
.... Notably, if the OS's system time is updated (e.g. atomic clock synchronization), Date.getTime() is also updated. now() is guaranteed to always be monotonically increasing, so it is not affected by the OS's system time -- it will always be wall-clock time (assuming your wall clock is not atomic.....
Optimise PostgreSQL for fast testing
...page_cost reflect your system's performance, ensure your effective_cache_size is correct, etc. Use EXPLAIN (BUFFERS, ANALYZE) to examine individual query plans, and turn the auto_explain module on to report all slow queries. You can often improve query performance dramatically just by creating an ap...
Why shouldn't all functions be async by default?
... of your operations are high latency, and those operations are causing the zombie infestation of async throughout the code.
if performance is the sole problem, surely some clever optimizations can remove the overhead automatically when it's not needed.
In theory, theory and practice are simila...
Multi-gradient shapes
... = new ShapeDrawable.ShaderFactory() {
@Override
public Shader resize(int width, int height) {
LinearGradient lg = new LinearGradient(0, 0, width, height,
new int[]{Color.GREEN, Color.GREEN, Color.WHITE, Color.WHITE},
new float[]{0,0.5f,.55f,1}, Shader.TileMod...
Spring DAO vs Spring ORM vs Spring JDBC
...no definitive mapping from one provider to the other. Relying on this is hazardous.
This is however a good idea to annotate your DAOs with @Repository, as the beans will be automatically added by the scan procedure. Further, Spring may add other useful features to the annotation.
Spring-JDBC
Spri...
How does having a dynamic variable affect performance?
...ts up a special version of the C# compiler that just has the metadata analyzer, the semantic analyzer for expressions, and an emitter that emits Expression Trees instead of IL.
The metadata analyzer uses Reflection to determine the type of the object in d1, and then passes that to the semantic ana...
Breadth First Vs Depth First
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87.6k2323 gold badges127127 silver badges219219 bronze badges
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Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
...he author wants its first commit to be empty (see blog post "How I initialize my Git repositories"):
$ GIT_AUTHOR_DATE="Thu, 01 Jan 1970 00:00:00 +0000" GIT_COMMITTER_DATE="Thu, 01 Jan 1970 00:00:00 +0000" git commit --allow-empty -m 'Initial commit'
Will give you:
(See the tree SHA1?)
You ca...
Can you explain the HttpURLConnection connection process?
...
user3306155
2333 bronze badges
answered Apr 12 '12 at 4:09
jmort253jmort253
31.2k99 gold badges8989...
Amazon S3 Change file download name
...
I guess your cross posted this questions to Amazon S3 forum, but for the sake of others I'd like to post the answer here:
If there is only ever one "user filename" for each S3 object, then you can set the Content-Disposition header on your s3 file to set the downloading ...