Easy memory sharing between machines and/or processes for Node.js
- A single variable (property) is shared between machines and/or processes
- When this variable value changes, it is updated on all other machines/processes
- Supported value types are JSON, String, Boolean and Number
- Sharing is done using a TCP socket
- Extremely simple and small. No other module dependency
- No guarantees of concurrent writes, last one stands
- No persistence. On restarts, it'll sync with other peers and get the most updated value
- It's actually copying data, not strictly sharing the same memory allocation
npm install amnesia
var mem = ;memconf = /* your configuration, see example below */;memdata = 1; // mem.data variable in all machines will have their value set to 1
When value changes
See what is happening/debug
When it was last updated
conf.json to your application directory and edit/add your ips/ports
memconf = ;
OR add it directly to your code
memconf ="host" : "10.0.1.2""port" : 7777"host" : "10.0.1.2""port" : 8888"host" : "10.0.1.6""port" : 8888
If you'll share on the same machine with different processes, duplicate the ip with different ports
All machines should have the same configuration with the current machine's ip and its peers.
How it works
It uses the
Object.defineProperty to add a custom setter and getter to the
data property on the
mem (amnesia) object.
When a value is set (i.e.
mem.data = 1) the custom setter is called.
The custom setter sets the value to the local variable and also write its value to the TCP socket for each other peer.
Other peers receive the new value and set them locally to their
mem.data. The 'change' event triggers.
When a new process/machine starts (or restarts), it gets the most updated value from its peers (sync request).
On machine 1:
node> var mem => memconf => memdata = jsontest : 123 // <-- set to some jsonjsontest: 123>
Then, on machine 2:
node> var mem => memconf = // <-- after adding config, a SYNC happens> memdata // <-- value for mem.data is already setjsontest: 123> memdata = jsontest: 456 // <-- set a new value>
Back to machine 1:
> memdata // <-- new value already on machine 1jsontest: 456>
Licensed under the MIT license.