How expensive are multiple requires on the same file on the same instance of Node JS?
My understanding of require (so far) is that it performs a traversal up the directory structure, looking for the module you're trying to import. Well, that's not exactly correct, but let's assume the directory traversal cost is negligible.
I have a module called BigModule. It has a lot of stuff in it, so there's some cost associated with loading it up with a require statement. Is importing it a hundred times a hundred times more expensive than importing it once, or is there some sort of caching mechanism which causes these scripts to share one BigModule instance? This is all happening on a single Node instance.
javascript typescript plugins
asked Nov 12 at 18:43
Brent Allard
109211
add a comment |
My understanding of require (so far) is that it performs a traversal up the directory structure, looking for the module you're trying to import. Well, that's not exactly correct, but let's assume the directory traversal cost is negligible.
I have a module called BigModule. It has a lot of stuff in it, so there's some cost associated with loading it up with a require statement. Is importing it a hundred times a hundred times more expensive than importing it once, or is there some sort of caching mechanism which causes these scripts to share one BigModule instance? This is all happening on a single Node instance.
javascript typescript plugins
asked Nov 12 at 18:43
Brent Allard
109211
add a comment |
My understanding of require (so far) is that it performs a traversal up the directory structure, looking for the module you're trying to import. Well, that's not exactly correct, but let's assume the directory traversal cost is negligible.
I have a module called BigModule. It has a lot of stuff in it, so there's some cost associated with loading it up with a require statement. Is importing it a hundred times a hundred times more expensive than importing it once, or is there some sort of caching mechanism which causes these scripts to share one BigModule instance? This is all happening on a single Node instance.
javascript typescript plugins
asked Nov 12 at 18:43
Brent Allard
109211
My understanding of require (so far) is that it performs a traversal up the directory structure, looking for the module you're trying to import. Well, that's not exactly correct, but let's assume the directory traversal cost is negligible.
I have a module called BigModule. It has a lot of stuff in it, so there's some cost associated with loading it up with a require statement. Is importing it a hundred times a hundred times more expensive than importing it once, or is there some sort of caching mechanism which causes these scripts to share one BigModule instance? This is all happening on a single Node instance.
javascript typescript plugins
javascript typescript plugins
asked Nov 12 at 18:43
Brent Allard
109211
asked Nov 12 at 18:43
Brent Allard
109211
asked Nov 12 at 18:43
Brent Allard
109211
asked Nov 12 at 18:43
Brent Allard
109211
asked Nov 12 at 18:43
Brent Allard
109211
109211
add a comment |
add a comment |
1 Answer
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require() caches calls by resolved filepath; require()ing the same file twice (even via symlink or different relative path) will not rerun the code.
answered Nov 12 at 18:44
SLaks
677k13816261748
add a comment |
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1 Answer
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1 Answer
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require() caches calls by resolved filepath; require()ing the same file twice (even via symlink or different relative path) will not rerun the code.
answered Nov 12 at 18:44
SLaks
677k13816261748
add a comment |
require() caches calls by resolved filepath; require()ing the same file twice (even via symlink or different relative path) will not rerun the code.
answered Nov 12 at 18:44
SLaks
677k13816261748
add a comment |
require() caches calls by resolved filepath; require()ing the same file twice (even via symlink or different relative path) will not rerun the code.
answered Nov 12 at 18:44
SLaks
677k13816261748
require() caches calls by resolved filepath; require()ing the same file twice (even via symlink or different relative path) will not rerun the code.
answered Nov 12 at 18:44
SLaks
677k13816261748
answered Nov 12 at 18:44
SLaks
677k13816261748
answered Nov 12 at 18:44
SLaks
677k13816261748
answered Nov 12 at 18:44
SLaks
677k13816261748
677k13816261748
add a comment |
add a comment |
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