大约有 15,000 项符合查询结果（耗时：0.0346秒） [XML]
Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...ter_initialize couldn't easily be moved to before_validation, before_save, etc. Chances are that eventually one of the devs on your team will execute something like MyModel.all.each perhaps for bulk processing of some kind, and thus run this initialization logic MyModel.count num of times.
...
AI2 Media Notification
...ed, this function gradually switches everything down (display, CPU, WiFi, etc.). In order to bypass Doze mode effectively, it is necessary to create a foreground service. A lot of useful background information can be found in the ZEBRA Developer Portal: Keeping your Android application running wh...
Is < faster than
...zero (equal) --> ZF = 1
jg - Jump if greater --> ZF = 0 and SF = OF
(etc...)
Example (Edited for brevity) Compiled with $ gcc -m32 -S -masm=intel test.c
if (a < b) {
// Do something 1
}
Compiles to:
mov eax, DWORD PTR [esp+24] ; a
cmp eax, DWORD...
Pass correct “this” context to setTimeout callback?
...n, you'd have solved this problem for this case, for map(), for forEach(), etc., etc., using less code, fewer CPU cycles, and less memory. ***See: Misha Reyzlin's answer.
– HoldOffHunger
Oct 20 '17 at 17:06
...
Maximum number of records in a MySQL database table
...4.16xlarge AWS instances (1 reader, 1 writer). Each of the machines had 64 CPU cores, 488GB of ram, 25Gbps network link, 64TB of disk. This scale of db was pushing both CPU and disk size limits and AWS does not provide any larger DB optimized instances. It was replaced with a simpler db schema that...
Method names for getting data [closed]
...u are
loading from an external source,
like a file or db.
I would not use
fetch/retrieve because they are too vague and get conflated with get and there is no unambiguous semantic associated with the terms.
Example: fetch implies that some entity needs to go and get something that is remote and bri...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
... RHEL/CentOS.
No need for priv, dorky binaries, hacky scripts, libpcap, etc. Win.
$ sar -n DEV 1 3
Linux 2.6.18-194.el5 (localhost.localdomain) 10/27/2010
02:40:56 PM IFACE rxpck/s txpck/s rxbyt/s txbyt/s rxcmp/s txcmp/s rxmcst/s
02:40:57 PM lo 0.00 0.00 ...
What does threadsafe mean?
...eed to perform common actions - disk i/o, outputting results to the screen etc. - these parts of the code will need to be written in such a way that they can handle being called from multiple threads, often at the same time. This will involve things like:
Working on copies of data
Adding locks aro...
What are the dangers when creating a thread with a stack size of 50x the default?
... know how to predict it - permissions, GC (which needs to scan the stack), etc - all could be impacted. I would be very tempted to use unmanaged memory instead:
var ptr = Marshal.AllocHGlobal(sizeBytes);
try
{
float* x = (float*)ptr;
DoWork(x);
}
finally
{
Marshal.FreeHGlobal(ptr);
}
...
How to deal with a slow SecureRandom generator?
...ized environment because it doesn't require any special hardware, only the CPU itself and a clock.
On Ubuntu/Debian:
apt-get install haveged
update-rc.d haveged defaults
service haveged start
On RHEL/CentOS:
yum install haveged
systemctl enable haveged
systemctl start haveged
Option 2. Reduce...