High Sitecore memory consumption

-

Case

We experienced a problem last week on a number of servers that steadily kept on using up memory.
After inspection it turned out that each and every page request was creating up-to 7 new caches for BlobId's. Since we saw the following in our logs:



As you can see, each of these caches took up 500KB and in our case (since 7 caches were created) this resulted in a 3,5MB of consumed memory on the server for each page request.
Furthermore, it turned out that these caches were not accessed or used at all but only kept on consuming valuable memory.

Find the problem and solution below so you never make the same mistake and don't have to embark on a wild goose-hunt to solve this one.

Okay, how did we fix this and what was causing it !?

First off, our sincerest thanks to the intervention of Sitecore support which helped us pinpoint the problem directly and made for a quick resolve.

Sitecore informed us that the creation of these cache entries is done when a new instance of a Sitecore Database object is created instead of using the Factory that helps provide these.

In other words:         new Database("web"); 

The reason that we had the problem appear so heavily is that the following code:
LanguageCollection configuredLanguages = LanguageManager.GetLanguages(new Database("web"));
 was used in a utility method for handling language information... and of course this method was called a number of times.


Where we should be using any of the below:  
var database = Sitecore.Data.Database.GetDatabase("web");
var database = Sitecore.Configuration.Factory.GetDatabase("web")

Or in the case where you just need the current context database:
var database = Sitecore.Context.Database;

Cool, any pitfalls though ?

Obviously no pitfalls exist here. The only important thing that has to be done is make sure NONE of your projects/code bases are still using the red-highlighted code above.

Comments

  1. UnknownOctober 21, 2014 at 4:19 PM

    Flail the developer that wrote that code! :-)

    All Sitecore documentation states clearly to use the GetDatabase function on either the Database or Factory classes. Stackoverflow has many posts regarding this common mistake as well. When you use a constructor you have to know what you're constructing...

    Deep code you'll see that Database.GetDatabase is merely a shortcut to Factory.GetDatabase and that Factory accesses your configuration to initialize the Database object. Furthermore it keeps a cache of those instances so they are only constructed once (preventing the memory leak you're observing).

    ReplyDelete
  2. Kris VerheireOctober 21, 2014 at 4:38 PM

    He is breathing no more :) Actually the main problem was not the main adoption of this approach, rather the fact that it snuck it's way in there somewhere, and finding it was the tricky part.
    The primary developer reaction was one of suprise on the fact that this was even (still) possible :)

    ReplyDelete

Post a Comment

Popular posts from this blog

Stupid exception: Device is not ready – System.IOException .net

-
When installing a Sitecore implementation from an development server environment to my laptop I ran into an absolutely stupid error. And it's great to have this kind of errors pop up from time to time even if you have been in the development world for so long and are still unable to fix it immediately. So, what error did I get? Device is not ready – System.IOException .net That is right... Nothing at all related to Sitecore. But then you start to doubt that as my stacktrace showed to Lucene [IOException: The device is not ready. ] System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath) +1091 System.IO.Directory.InternalCreateDirectory(String fullPath, String path, Object dirSecurityObj, Boolean checkHost) +1413 System.IO.Directory.InternalCreateDirectoryHelper(String path, Boolean checkHost) +92 Sitecore.IO.FileUtil.EnsureFolder(String path) +128 Sitecore.ContentSearch.LuceneProvider.LuceneIndex.CreateDirectory(String folder) +100 Sitecore.Co...
Read more

Date Ranges in C#

-
DateRange utility class Throughout development there are a number of typical things that tend to recur. One of these is implementing a means to display start and end dates for News, Events, Symposiums, Lives etc etc Writing a little class that manages printing these dates seemed like a necessary task that just had to be done in order to make this tedious task be a thing of the past. Therefore I created my "DateRange" class (what's in a name) that should handle this entirely for you. The Idea The intriquities of displaying a datetime range should be an abstraction. You should only need to worry about passing the correct dates (start and end - if applicable) to the Utility class combined with an optional formatting. The class can be entirely configured through use of Enumerations for all the separate settings such as DayFormat etc. An additional class was used to implement this utility, the StringValue attribute class. You can easily use thie class to a...
Read more

Sitecore 8.2 in-depth preview + 8.3 update info and Sitecore Ecommerce information

-
Image
During the last Sitecore User group session here in Belgium, Ryan Donovan was featured as the central speaker. The following two topics were on the agenda: Sitecore Commerce An in-depth information on 8.2 and 8.3 I was impressed by the drive behind Ryan and his team(s). It emphasized the drive that is pushing Sitecore forward. Sitecore is putting a lot of effort in producing well hardened and tested product releases that bring new features and rich applications. Sitecore Commerce Previous Sitecore commerce solutions were structured around either SCpbCS and SCpbMD. However, the vNext commerce product has been newly developed from the ground up. Previously, the commerce solution focussed itself around the architecture of Commerce Server to provide and API, manage the products and to derive the entire feature set from. With this Commerce vNext solution, Sitecore has set forward the aspiration to become one of the market leaders in commerce. The fist aim is to focu...
Read more