Fixing high Memory usage / File sizes exporting from Ad-Hoc vs Studio based reports

Use case:

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Customer has noticed that there appears to be a large difference in PDF output sizes between reports produced in Ad-Hoc vs similar reports produced within Studio and run on the server. This size difference appears to affect both the size of the file and the amount of time / memory used on the server whilst the export is being generated.  The amount of time to produce the files and the resultant file sizes vary hugely, sizes are below: 

Studio Report : 28,764 KB 

Ad-Hoc Report : 196,728 KB 

The page counts between the two report differ slightly but that is because the row count per page is slightly different - 28 rows on the studio report vs 29 on the ad-hoc report, so the studio based report actually has more pages than the ad-hoc - The page size is also slightly different but I wouldn't think it was enough of a difference to be a problem (14in * 10in for Studio and 11in * 11in for ad-hoc).  Also, customer has also noticed that the two exports appear to create different PDF versions - 1.5 for the Studio report and 1.4 for the ad-hoc report. 

Issue:

An example customer was working on  - 200,000 rows with 33 columns (again, tested reports written in Studio one Ad-Hoc):

• Studio report - JRS memory reached 1.9GB while report was executing and returned file was 35.4MB
• Ad-Hoc report - JRS memory reached 4.97GB and then hung tomcat

JRS did not produce an out of memory error but tomcat completely stopped responding.  Clearly such a large increase, both in terms of memory usage and file size has (potentially at least) quite a large impact on our hosted systems which are often running tens of customers per instance and potentially thousands of users.

Resolution:

The Adhoc PDF is much bigger because it includes 508 tags by default. If you edit the Adhoc report's JRXML and set the net.sf.jasperreports.export.pdf.tagged property to false, it will produce a 4MB PDF file:

 <property name="net.sf.jasperreports.export.pdf.tagged" value="false"/>

Unfortunately, this property is hard coded. As far as I can see in the code, the property is always set to true for Adhoc reports. It overrides both template properties and global properties. Therefore I don't think there's a way to globally set it to false. There is an enhancement request JS-34525 for ability to set this property globally.

So, at this moment this property has to be defined per Adhoc Report JRXML file.