# HG changeset patch
# User Sebastien Jodogne <s.jodogne@gmail.com>
# Date 1474888042 -7200
# Node ID 23d5a5a84287056029c2926223f52debd6f76525
# Parent  cccf3f21aee8201c948ff8136468cc1a5b8456a2
performance

diff -r cccf3f21aee8 -r 23d5a5a84287 Sphinx/source/faq/troubleshooting.rst
--- a/Sphinx/source/faq/troubleshooting.rst	Mon Sep 19 09:11:06 2016 +0200
+++ b/Sphinx/source/faq/troubleshooting.rst	Mon Sep 26 13:07:22 2016 +0200
@@ -45,6 +45,21 @@
   most recent version of the mainline), or versions more recent than
   ``jodogne/orthanc:1.1.0``.
 
+* **Orthanc slows down if storing many files**: The default database
+  engine that is built in Orthanc is `SQLite
+  <https://www.sqlite.org/>`__. As SQLite is above all a lightweight
+  database engine, it is not designed to `store very large datasets
+  <https://www.sqlite.org/whentouse.html>`__. If you are sure that you
+  have properly disabled run-time debug assertions (cf. above), but
+  still experience degradation in performance over time, you should
+  seriously consider switching to a more scalable database engine. To
+  this end, you can notably check out the :ref:`official PostgreSQL
+  plugin <postgresql>`.
+
+  As a rule of thumb, the performance of the default SQLite engine
+  built in Orthanc should run fine up to about 50,000 DICOM instances.
+
+
 * **Orthanc Explorer is slow under Windows on the localhost**:
 
   - Favor ``127.0.0.1`` instead of ``localhost`` when specifying the