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SqlException from Entity Framework - New transaction is not allowed because there are other threads
...likely to have a clustered index.
This version will query the database in batches of 100. Note that SaveChanges() is called for each entity.
If you want to improve your throughput dramatically, you should call SaveChanges() less frequently. Use code like this instead:
foreach (var chunk in clie...
How efficient is locking an unlocked mutex? What is the cost of a mutex?
...ng): (1) a flag indicating whether the mutex is locked or not and (2) wait queue.
Change of the flag is just few instructions and normally done without system call. If mutex is locked, syscall will happen to add the calling thread into wait queue and start the waiting. Unlocking, if the wait queue ...
“NODE_ENV” is not recognized as an internal or external command, operable command or batch file
... is not recognized as an internal or external command, operable program or batch file.
– Rod Lima
Mar 22 '18 at 13:53
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show 2 more comments...
How to increase scrollback buffer size in tmux?
...ght use a command like this (from a shell):
tmux set-option history-limit 5000 \; new-window
For (the initial pane of the initial window in) a new session you will need to set the “global” history-limit before creating the session:
tmux set-option -g history-limit 5000 \; new-session
Note:...
Thread Safety in Python's dictionary
... variable assignment (since this in turn depends on dictionaries).
Use the Queue module's Queue data type as the preferred way to communicate data between threads. Otherwise, use the threading module and its locking primitives. Learn about the proper use of condition variables so you can use threadi...
Batch file: Find if substring is in string (not in a file)
In a batch file, I have a string abcdefg . I want to check if bcd is in the string.
10 Answers
...
How can I efficiently select a Standard Library container in C++11?
...ontainers
and then you can build several adapters on top of them: stack, queue, priority_queue. I will leave the adapters out here, they are sufficiently specialized to be recognizable.
Question 1: Associative ?
If you need to easily search by one key, then you need an associative container
I...
iOS: how to perform a HTTP POST request?
...nwards can also use + (void)sendAsynchronousRequest:(NSURLRequest )request queue:(NSOperationQueue *)queue completionHandler:(void (^)(NSURLResponse, NSData*, NSError*))handler
– chunkyguy
Jun 26 '13 at 0:54
...
Remove Application Insight from application on Visual Studio 2013
...ion(config){
function r(config){t[config]=function(){var i=arguments;t.queue.push(function(){t[config].apply(t,i)})}}var t={config:config},u=document,e=window,o="script",s=u.createElement(o),i,f;for(s.src=config.url||"//az416426.vo.msecnd.net/scripts/a/ai.0.js",u.getElementsByTagName(o)[0].paren...
Change from SQLite to PostgreSQL in a fresh Rails project
...dapter: sqlite3
# database: db/development.sqlite3
# pool: 5
# timeout: 5000
development:
adapter: postgresql
encoding: unicode
database: f3_development
pool: 5
username: f3
password:
#test:
# adapter: sqlite3
# database: db/test.sqlite3
# pool: 5
# timeout: 5000
test:
adapte...