Thread-safe alternative of global variables
I want to use multi-thread Puma as a production server so my code should be thread-safe.
I read that the usage of global variables isn't thread-safe. What is the alternative to global variables in this case?
I used global variables (without value changes) as Redis keys for set/get etc.
#initializers/redis.rb
$DRIVER_LOCATIONS = "driver_locations"
and in code
REDIS.with do |conn|
conn.geoadd($DRIVER_LOCATIONS, latitude, longitude, id)
end
Or there is no need to change something?
ruby-on-rails ruby multithreading ruby-on-rails-5
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
add a comment |
I want to use multi-thread Puma as a production server so my code should be thread-safe.
I read that the usage of global variables isn't thread-safe. What is the alternative to global variables in this case?
I used global variables (without value changes) as Redis keys for set/get etc.
#initializers/redis.rb
$DRIVER_LOCATIONS = "driver_locations"
and in code
REDIS.with do |conn|
conn.geoadd($DRIVER_LOCATIONS, latitude, longitude, id)
end
Or there is no need to change something?
ruby-on-rails ruby multithreading ruby-on-rails-5
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
1
If you're only reading them, then you should be fine. Most/all problems arise when you try to concurrently write to the same place. BTW, why a global var here, and not a constant?
– Sergio Tulentsev
Jan 19 at 19:31
@anothermh: oh, but you cause total chaos in your app with a single-threaded database. Without a database at all, even.
– Sergio Tulentsev
Jan 19 at 20:46
@anothermh: I was saying that the single-threaded nature of redis has nothing to do with the amount of corruption/damage that an improperly implemented multi-threaded app can do to itself.
– Sergio Tulentsev
Jan 19 at 21:36
add a comment |
I want to use multi-thread Puma as a production server so my code should be thread-safe.
I read that the usage of global variables isn't thread-safe. What is the alternative to global variables in this case?
I used global variables (without value changes) as Redis keys for set/get etc.
#initializers/redis.rb
$DRIVER_LOCATIONS = "driver_locations"
and in code
REDIS.with do |conn|
conn.geoadd($DRIVER_LOCATIONS, latitude, longitude, id)
end
Or there is no need to change something?
ruby-on-rails ruby multithreading ruby-on-rails-5
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
I want to use multi-thread Puma as a production server so my code should be thread-safe.
I read that the usage of global variables isn't thread-safe. What is the alternative to global variables in this case?
I used global variables (without value changes) as Redis keys for set/get etc.
#initializers/redis.rb
$DRIVER_LOCATIONS = "driver_locations"
and in code
REDIS.with do |conn|
conn.geoadd($DRIVER_LOCATIONS, latitude, longitude, id)
end
Or there is no need to change something?
ruby-on-rails ruby multithreading ruby-on-rails-5
ruby-on-rails ruby multithreading ruby-on-rails-5
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
asked Jan 19 at 18:42
ViT-Vetal-ViT-Vetal-
1,12411023
1,12411023
1
If you're only reading them, then you should be fine. Most/all problems arise when you try to concurrently write to the same place. BTW, why a global var here, and not a constant?
– Sergio Tulentsev
Jan 19 at 19:31
@anothermh: oh, but you cause total chaos in your app with a single-threaded database. Without a database at all, even.
– Sergio Tulentsev
Jan 19 at 20:46
@anothermh: I was saying that the single-threaded nature of redis has nothing to do with the amount of corruption/damage that an improperly implemented multi-threaded app can do to itself.
– Sergio Tulentsev
Jan 19 at 21:36
add a comment |
1
If you're only reading them, then you should be fine. Most/all problems arise when you try to concurrently write to the same place. BTW, why a global var here, and not a constant?
– Sergio Tulentsev
Jan 19 at 19:31
@anothermh: oh, but you cause total chaos in your app with a single-threaded database. Without a database at all, even.
– Sergio Tulentsev
Jan 19 at 20:46
@anothermh: I was saying that the single-threaded nature of redis has nothing to do with the amount of corruption/damage that an improperly implemented multi-threaded app can do to itself.
– Sergio Tulentsev
Jan 19 at 21:36
1
1
If you're only reading them, then you should be fine. Most/all problems arise when you try to concurrently write to the same place. BTW, why a global var here, and not a constant?
– Sergio Tulentsev
Jan 19 at 19:31
If you're only reading them, then you should be fine. Most/all problems arise when you try to concurrently write to the same place. BTW, why a global var here, and not a constant?
– Sergio Tulentsev
Jan 19 at 19:31
@anothermh: oh, but you cause total chaos in your app with a single-threaded database. Without a database at all, even.
– Sergio Tulentsev
Jan 19 at 20:46
@anothermh: oh, but you cause total chaos in your app with a single-threaded database. Without a database at all, even.
– Sergio Tulentsev
Jan 19 at 20:46
@anothermh: I was saying that the single-threaded nature of redis has nothing to do with the amount of corruption/damage that an improperly implemented multi-threaded app can do to itself.
– Sergio Tulentsev
Jan 19 at 21:36
@anothermh: I was saying that the single-threaded nature of redis has nothing to do with the amount of corruption/damage that an improperly implemented multi-threaded app can do to itself.
– Sergio Tulentsev
Jan 19 at 21:36
add a comment |
1 Answer
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As stated in the comments, you should probably use a constant there instead of a global variable
#initializers/redis.rb
DRIVER_LOCATIONS = "driver_locations"
# ...
REDIS.with do |conn|
conn.geoadd(DRIVER_LOCATIONS, latitude, longitude, id)
end
Using the global variable shouldn't be that bad in your use case as it's set during initialization and I'm assuming that it's only done once.
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
add a comment |
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As stated in the comments, you should probably use a constant there instead of a global variable
#initializers/redis.rb
DRIVER_LOCATIONS = "driver_locations"
# ...
REDIS.with do |conn|
conn.geoadd(DRIVER_LOCATIONS, latitude, longitude, id)
end
Using the global variable shouldn't be that bad in your use case as it's set during initialization and I'm assuming that it's only done once.
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
add a comment |
As stated in the comments, you should probably use a constant there instead of a global variable
#initializers/redis.rb
DRIVER_LOCATIONS = "driver_locations"
# ...
REDIS.with do |conn|
conn.geoadd(DRIVER_LOCATIONS, latitude, longitude, id)
end
Using the global variable shouldn't be that bad in your use case as it's set during initialization and I'm assuming that it's only done once.
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
add a comment |
As stated in the comments, you should probably use a constant there instead of a global variable
#initializers/redis.rb
DRIVER_LOCATIONS = "driver_locations"
# ...
REDIS.with do |conn|
conn.geoadd(DRIVER_LOCATIONS, latitude, longitude, id)
end
Using the global variable shouldn't be that bad in your use case as it's set during initialization and I'm assuming that it's only done once.
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
As stated in the comments, you should probably use a constant there instead of a global variable
#initializers/redis.rb
DRIVER_LOCATIONS = "driver_locations"
# ...
REDIS.with do |conn|
conn.geoadd(DRIVER_LOCATIONS, latitude, longitude, id)
end
Using the global variable shouldn't be that bad in your use case as it's set during initialization and I'm assuming that it's only done once.
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
answered Jan 21 at 11:42
Diego CamargoDiego Camargo
11
11
add a comment |
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If you're only reading them, then you should be fine. Most/all problems arise when you try to concurrently write to the same place. BTW, why a global var here, and not a constant?
– Sergio Tulentsev
Jan 19 at 19:31
@anothermh: oh, but you cause total chaos in your app with a single-threaded database. Without a database at all, even.
– Sergio Tulentsev
Jan 19 at 20:46
@anothermh: I was saying that the single-threaded nature of redis has nothing to do with the amount of corruption/damage that an improperly implemented multi-threaded app can do to itself.
– Sergio Tulentsev
Jan 19 at 21:36