diff --git a/NEWS.md b/NEWS.md
index 3a76dce8..2190f597 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -8,11 +8,11 @@ Announcements:
 - Cache control header fine tuning. Set a shorter value for "max-age" directive if there is no way to know when to trigger the invalidation.
 - Update deps:
   - Update `cartodb-query-tables` to version [`0.5.0`](https://github.com/CartoDB/node-cartodb-query-tables/releases/tag/0.5.0)
-  - Upgrade `windshaft` to [`5.5.1`](https://github.com/CartoDB/Windshaft/blob/5.5.1/NEWS.md#version-551):
+  - Upgrade `windshaft` to [`5.6.0`](https://github.com/CartoDB/Windshaft/blob/5.6.0/NEWS.md#version-560):
     - Upgrade grainstore to [`2.0.1`](https://github.com/CartoDB/grainstore/releases/tag/2.0.1)
     - Update @carto/mapnik to [`3.6.2-carto.16`](https://github.com/CartoDB/node-mapnik/blob/v3.6.2-carto.16/CHANGELOG.carto.md#362-carto16).
     - Update turbo-carto to [`0.21.2`](https://github.com/CartoDB/turbo-carto/releases/tag/0.21.2)
-    - Upgrade `@carto/cartonik` to version [0.6.1](https://github.com/CartoDB/cartonik/blob/master/CHANGELOG.md#v061-2019-07-10).
+    - Upgrade `@carto/cartonik` to version [`0.7.0`](https://github.com/CartoDB/cartonik/blob/v0.7.0/CHANGELOG.md#cartonik-changelog).
 
 ## 7.1.0
 Released 2019-05-06
diff --git a/lib/cartodb/api/api-router.js b/lib/cartodb/api/api-router.js
index af82a3b8..14c7acec 100644
--- a/lib/cartodb/api/api-router.js
+++ b/lib/cartodb/api/api-router.js
@@ -100,7 +100,9 @@ module.exports = class ApiRouter {
 
         const tileBackend = new windshaft.backend.Tile(rendererCache);
         const attributesBackend = new windshaft.backend.Attributes();
-        const previewBackend = new windshaft.backend.Preview(rendererCache);
+        const concurrency = serverOptions.renderer.mapnik.poolSize +
+                            serverOptions.renderer.mapnik.poolMaxWaitingClients;
+        const previewBackend = new windshaft.backend.Preview(rendererCache, { concurrency });
         const mapValidatorBackend = new windshaft.backend.MapValidator(tileBackend, attributesBackend);
         const mapBackend = new windshaft.backend.Map(rendererCache, mapStore, mapValidatorBackend);
 
diff --git a/package-lock.json b/package-lock.json
index 498aad19..b8f8c7f0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -5,9 +5,9 @@
   "requires": true,
   "dependencies": {
     "@carto/cartonik": {
-      "version": "0.6.1",
-      "resolved": "https://registry.npmjs.org/@carto/cartonik/-/cartonik-0.6.1.tgz",
-      "integrity": "sha512-7tRnEe8JTGzbYxBcsXhneWzK2HVP/Fc4KcI0PNIgMAUsu3q2Yz3tikA9/OoT9PtGvcOmqNn6CwfVibBKwYO23Q==",
+      "version": "0.7.0",
+      "resolved": "https://registry.npmjs.org/@carto/cartonik/-/cartonik-0.7.0.tgz",
+      "integrity": "sha512-LD5HBx3/hUL4492I++rspGJh2bcoOjLAHBE8cOLi2fyqIK0NS5bekXrz9mEWY/Ie9xLDeKn9s89FTbl7IhrLrw==",
       "requires": {
         "@carto/mapnik": "3.6.2-carto.16",
         "@mapbox/sphericalmercator": "^1.1.0",
@@ -4040,11 +4040,11 @@
       "integrity": "sha1-tDFbtCFKPXBY6+7okuE/ok2YsHU="
     },
     "windshaft": {
-      "version": "5.5.1",
-      "resolved": "https://registry.npmjs.org/windshaft/-/windshaft-5.5.1.tgz",
-      "integrity": "sha512-Z8ChaxzBThnYCaSQsJJ5uWdNlTQRBndXvefn8DCaU8pikGfG1kcUD6IGE306MziljNDikKJC5XKf5Dmx6Awt5g==",
+      "version": "5.6.0",
+      "resolved": "https://registry.npmjs.org/windshaft/-/windshaft-5.6.0.tgz",
+      "integrity": "sha512-yXEdmrbOChYnL6VQBLW/uX6kfc68+dd26z3KCAG8X/VMnhhyXBqYOsttnMYO5SNqCyzuj5gu/pG06jRXwtN23g==",
       "requires": {
-        "@carto/cartonik": "^0.6.1",
+        "@carto/cartonik": "^0.7.0",
         "@carto/mapnik": "3.6.2-carto.16",
         "canvas": "^2.4.1",
         "carto": "github:cartodb/carto#0.15.1-cdb5",
diff --git a/package.json b/package.json
index 0bd04ffe..fdd3e0b6 100644
--- a/package.json
+++ b/package.json
@@ -49,7 +49,7 @@
     "step-profiler": "0.3.0",
     "turbo-carto": "0.21.2",
     "underscore": "1.6.0",
-    "windshaft": "^5.5.1",
+    "windshaft": "^5.6.0",
     "yargs": "11.1.0"
   },
   "devDependencies": {
diff --git a/test/acceptance/ported/support/ported_server_options.js b/test/acceptance/ported/support/ported_server_options.js
index b0fddbe2..cf040a48 100644
--- a/test/acceptance/ported/support/ported_server_options.js
+++ b/test/acceptance/ported/support/ported_server_options.js
@@ -50,6 +50,7 @@ module.exports = _.extend({}, serverOptions, {
     renderer: {
         mapnik: {
             poolSize: 4,//require('os').cpus().length,
+            poolMaxWaitingClients: 32,
             metatile: 1,
             bufferSize: 64,
             snapToGrid: false,