added checks to prevent repeat allocation in Speculative JIT

dispatch_system/constants.json

@@ -28,7 +28,10 @@
     "autoscalar_metrics": {
         "open_request_threshold": 100
     },
-    "speculative_deployment": false,
-    "JIT_deployment": false,
+    "metrics": {
+        "alpha": 0.7
+    },
+    "speculative_deployment": true,
+    "JIT_deployment": true,
     "id_size": 20
 }

dispatch_system/dispatch_manager/explicit_chain_handler.js

@@ -8,6 +8,8 @@ const fetch = require('node-fetch')
 const constants = require('../constants.json')
 const secrets = require('./secrets.json')
 const operator = require('./operator')
+const sharedStructures = require('./shared_structures')
+
 let metadataDB = `http://${secrets.couchdb_username}:${secrets.couchdb_password}@${constants.couchdb_host}`
 metadataDB = metadataDB + "/" + constants.function_db_name + "/"
 
@@ -17,7 +19,8 @@ metricsDB = metricsDB + "/" + constants.metrics_db_name + "/"
 const logger = libSupport.logger
 
 const registry_url = constants.registry_url
-
+let functionToResource = sharedStructures.functionToResource,
+    db = sharedStructures.db
 router.post('/deploy', (req, res) => {
     
     // let runtime = req.body.runtime
@@ -200,7 +203,6 @@ router.post('/execute/:id', (req, res) => {
             .then(data => {
                 aliases = data
                 let payload = JSON.parse(req.body.data)
-                console.log(payload);
                 speculative_deployment(aliases, mapPlanner);
                 orchestrator(res, payload, map, aliases, {})
             })
@@ -311,18 +313,10 @@ async function speculative_deployment(aliases, map) {
                 console.log(mod, metadata, aliases[mod].alias);
 
                 let url = metricsDB + aliases[mod].alias
-                console.log(url);
-
                 let data = libSupport.fetchData(url)
-                console.log(data);
-
                 getData.push(data)
             } else {
-                let payload = [{
-                    topic: constants.topics.hscale,
-                    messages: JSON.stringify({ "runtime": metadata.runtime, "functionHash": aliases[mod].alias })
-                }]
-                notify(payload)
+                notify(metadata.runtime, aliases[mod].alias)
             }
         }
         if (constants.JIT_deployment) {
@@ -354,15 +348,11 @@ async function speculative_deployment(aliases, map) {
                                     maxWait = done[dependency]
                             }
                             if (flag) {
-                                console.log("notifying", mod);
+                                console.log("notification set", mod);
                                 let notifyTime = ((maxWait - dataMap[aliases[mod].alias][metadata.runtime].starttime) > 0) ?
                                     maxWait - dataMap[aliases[mod].alias][metadata.runtime].starttime : 0
                                 console.log(mod, "max wait", maxWait, "notify time:", notifyTime);
-                                let payload = [{
-                                    topic: constants.topics.hscale,
-                                    messages: JSON.stringify({ "runtime": metadata.runtime, "functionHash": aliases[mod].alias })
-                                }]
-                                setTimeout(notify, notifyTime, payload)
+                                setTimeout(notify, notifyTime, metadata.runtime, aliases[mod].alias)
                                 done[mod] = maxWait + dataMap[aliases[mod].alias][metadata.runtime].warmstart
                                 if (toBeDone.has(mod))
                                     delete toBeDone[mod]
@@ -405,8 +395,18 @@ function readMap(filename, alias = false) {
     })
 }
 
-function notify(payload) {
+function notify(runtime, functionHash) {
+    console.log("check map: ", functionToResource.has(functionHash + runtime));
+    if (!functionToResource.has(functionHash + runtime) && !db.has(functionHash + runtime)) {
+        let payload = [{
+            topic: constants.topics.hscale,
+            messages: JSON.stringify({ runtime, functionHash })
+        }]
         libSupport.producer.send(payload, function () { })
+    } else {
+        console.log("resource already present: skipping speculation");
+        
+    }
 }
 
 function createDirectory(path) {
@@ -423,4 +423,10 @@ function createDirectory(path) {
     })
 }
 
-module.exports = router;
+function initialise(functionToResource) {
+    this.functionToResource = functionToResource
+}
+
+module.exports = {
+    router, initialise
+}

dispatch_system/dispatch_manager/index.js

@@ -13,6 +13,7 @@ const fetch = require('node-fetch');
 const swStats = require('swagger-stats');
 const apiSpec = require('./swagger.json');
 const util = require('util')
+const sharedStructures = require('./shared_structures')
 
 /**
  * URL to the couchdb database server used to store function metadata
@@ -30,14 +31,14 @@ let date = new Date();
 let log_channel = constants.topics.log_channel
 
 let usedPort = new Map(), // TODO: remove after integration with RM
-    db = new Map(), // queue holding request to be dispatched
-    resourceMap = new Map(), // map between resource_id and resource details like node_id, port, associated function etc
-    functionToResource = new Map(), // a function to resource map. Each map contains a minheap of
+    db = sharedStructures.db, // queue holding request to be dispatched
+    resourceMap = sharedStructures.resourceMap, // map between resource_id and resource details like node_id, port, associated function etc
+    functionToResource = sharedStructures.functionToResource, // a function to resource map. Each map contains a minheap of
                                    // resources associated with the function
-    workerNodes = new Map(), // list of worker nodes currently known to the DM
-    functionBranchTree = new Map() // a tree to store function branch predictions
-    
+    workerNodes = sharedStructures.workerNodes, // list of worker nodes currently known to the DM
+    functionBranchTree = sharedStructures.functionBranchTree // a tree to store function branch predictions
     
+chainHandler.initialise(functionToResource)
 let kafka = require('kafka-node'),
     Producer = kafka.Producer,
     client = new kafka.KafkaClient({ 
@@ -64,11 +65,10 @@ app.use(morgan('combined', {
 app.use(express.json());
 app.use(express.urlencoded({ extended: true }));
 const file_path = __dirname + "/repository/"
-
 app.use('/repository', express.static(file_path)); // file server hosting deployed functions
 app.use(fileUpload())
 app.use(swStats.getMiddleware({ swaggerSpec: apiSpec })); // statistics middleware
-app.use('/serverless/chain', chainHandler); // chain router (explicit_chain_handler.js) for handling explicit chains
+app.use('/serverless/chain', chainHandler.router); // chain router (explicit_chain_handler.js) for handling explicit chains
 let requestQueue = []
 
 const WINDOW_SIZE = 10
@@ -428,7 +428,11 @@ consumer.on('message', function (message) {
             functionHash = message.functionHash
         logger.info(`Generated new resource ID: ${resource_id} for runtime: ${runtime}`);
         console.log("Resource Status: ", functionToResource);
+        if (!functionToResource.has(functionHash + runtime) && !db.has(functionHash + runtime)) {
+            console.log("adding db");
             
+            db.set(functionHash + runtime, [])
+        }
         /**
          * Request RM for resource
          */
@@ -451,6 +455,7 @@ consumer.on('message', function (message) {
             }),
             partition: 0
         }]
+        
         producer.send(payloadToRM, () => {
             // db.set(functionHash + runtime, { req, res })
             console.log("sent rm");

dispatch_system/dispatch_manager/metrics.js

@@ -9,7 +9,7 @@ const prom = require('prom-client');
 const Registry = prom.Registry;
 const register = new Registry();
 
-const alpha = 0.99
+const alpha = constants.metrics.alpha
 let log_channel = constants.topics.log_channel,
     metrics = {  }
 

dispatch_system/dispatch_manager/shared_structures.js

+let db = new Map(), // queue holding request to be dispatched
+    resourceMap = new Map(), // map between resource_id and resource details like node_id, port, associated function etc
+    functionToResource = new Map(), // a function to resource map. Each map contains a minheap of
+                                    // resources associated with the function
+    workerNodes = new Map(), // list of worker nodes currently known to the DM
+    functionBranchTree = new Map() // a tree to store function branch predictions
+
+
+module.exports = {
+    db, functionBranchTree, functionToResource, workerNodes, resourceMap
+}
\ No newline at end of file