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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
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Nate C was close, but not quite.
From the docs:
You can evaluate a QuerySet in the following ways:
Iteration. A QuerySet is iterable, and it executes its database query the first time you iterate over it. For example, this will print the headline...
How can bcrypt have built-in salts?
...tor has been pre-configured. Collect a password.
Derive an encryption key from the password using the salt and cost factor. Use it to encrypt a well-known string. Store the cost, salt, and cipher text. Because these three elements have a known length, it's easy to concatenate them and store them in...
Where do you include the jQuery library from? Google JSAPI? CDN?
... I agree with all three of your reasons which is why I include jquery from Google on my production sites. Instead of the the js dynamic injection for SSL pages I just reference url in a script tag without the protocol specified. Seems to work fine for me. <script src="//ajax.google...">...
nodejs how to read keystrokes from stdin
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For those finding this answer since this capability was stripped from tty, here's how to get a raw character stream from stdin:
var stdin = process.stdin;
// without this, we would only get streams once enter is pressed
stdin.setRawMode( true );
// resume stdin in the parent process (no...
How to “hibernate” a process in Linux by storing its memory to disk and restoring it later?
.... And then later on, I can 'resume the process', i.e, reading all the data from memory and put it back to RAM and I can continue with my process?
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shortcut for creating a Map from a List in groovy?
...tMap{[it.value, it.key]} == [2:1, 4:3]
and here I use it to create a map from a list
[1,2].collectMap{[it,it]} == [1:1, 2:2]
now I just pop this into a class that gets called as my app is starting and this method is available throughout my code.
EDIT:
to add the method to all arrays...
Objec...
Why is the C++ STL is so heavily based on templates? (and not on *interfaces*)
I mean, aside from its obligating name (the Standard Template Library)...
13 Answers
1...
What is the meaning of “non temporal” memory accesses in x86
...30.html . I couldn't find more precise references, I only heard about this from guys whose job is to implement processor simulators.
– Pascal Cuoq
May 4 '10 at 20:03
2
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Which is the preferred way to concatenate a string in Python?
... this case, append/join is slower.
So where does this recommendation come from? Python 2?
a += b:
0.165287017822
a.append(b):
0.0132720470428
a.join(a):
0.114929914474
Well, append/join is marginally faster there if you are using extremely long strings (which you usually aren't, what would you h...
IOCTL Linux device driver [closed]
...where you set up a file under /sys/ and read/write that to get information from and to the driver. An example of how to set this up:
static ssize_t mydrvr_version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%s\n", DRIVER_RELEASE);
}
static ...