[jira] [Commented] (FOP-2190) decrease PDF file size when CS are enabled
[ https://issues.apache.org/jira/browse/FOP-2190?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14549109#comment-14549109 ] Andreas L. Delmelle commented on FOP-2190: -- Reading the comment about String.substring potentially causing a "significant performance and memory allocation penalty" actually made me chuckle slightly... Do we have any measurements/numbers in that regard? How many calls to substring() are we talking about? How long, on average, is the base string? How long are the substrings, typically? I am not at all convinced this is an issue to be worried about, since: 1° In older Java versions (pre 1.7r6), String.substring() runs in constant time and just returns a new instance wrapped around the same char array as the original, taking up the space of a reference and two ints only for the duration of the call (see also 2°) 2° Even in more recent Java versions, those newly allocated String instances, with their own char arrays, have a very short lifespan (= just the duration of the drawTextD* executions), so any allocated memory for the new char array can be reclaimed as soon as the method is exited. Because of that short lifespan, the instances and arrays in question will likely never even leave the stack. The only scenario where the newer implementation (= a completely independent String instance) would have a "significant" impact on performance and memory would be the case where one repeatedly takes rather large substring from another very large string. In most common use cases on modern systems, however, the difference will be unnoticeable, and performance may even benefit, as Luis' measurements seem to demonstrate (although I cannot immediately explain why that would be --Strings are immutable, so no need to synchronize any mutations...?) > decrease PDF file size when CS are enabled > --- > > Key: FOP-2190 > URL: https://issues.apache.org/jira/browse/FOP-2190 > Project: Fop > Issue Type: Improvement > Components: renderer/pdf >Affects Versions: 1.1, trunk >Reporter: Luis Bernardo > Attachments: fop-2190.patch > > > when CS are enabled, the current code may make use of the operators Td and Tj > in situations where TJ would be appropriate leading to an increase in file > size. note: this happens in the PDFPainter.drawText(). -- This message was sent by Atlassian JIRA (v6.3.4#6332)
[jira] [Commented] (FOP-2190) decrease PDF file size when CS are enabled
[ https://issues.apache.org/jira/browse/FOP-2190?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13559507#comment-13559507 ] Luis Bernardo commented on FOP-2190: in my tests performance was greatly improved by this change. I did not measure though how memory allocation was impacted. the test was the following: - use a long text document (around 100 pages) with the Arial font - generate the PDF using the servlet that ships with FOP, making sure it uses a proper configured fop.xconf (i.e., uses the Arial font and does not disable CS) - use ab (apache benchmark) to make 100 requests and look at the time measurements (after allowing for warm up) note that I also added some time measurements inside the servlet to confirm the improvement in performance was not due to reduced HTTP transfer times (i.e., was really in the generation of the document) it is possible that some different tests show other results. > decrease PDF file size when CS are enabled > --- > > Key: FOP-2190 > URL: https://issues.apache.org/jira/browse/FOP-2190 > Project: Fop > Issue Type: Improvement > Components: pdf >Affects Versions: 1.1, trunk >Reporter: Luis Bernardo > Attachments: fop-2190.patch > > > when CS are enabled, the current code may make use of the operators Td and Tj > in situations where TJ would be appropriate leading to an increase in file > size. note: this happens in the PDFPainter.drawText(). -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira
[jira] [Commented] (FOP-2190) decrease PDF file size when CS are enabled
[ https://issues.apache.org/jira/browse/FOP-2190?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13559323#comment-13559323 ] Glenn Adams commented on FOP-2190: -- i've implemented a portion of this patch already in FOP-2195, however I am not prepared to apply the code that switches between the DX/DP text drawing functions since it imposes a significant performance and memory allocation penalty in order to reduce PDF output size; in particular, the use of String.substring() will cause a great amount of additional String allocation that would not otherwise be present; in order to apply this additional optimization, I think we need to: (1) create a PDF renderer configuration option that allows the user to express whether to optimize PDF size or processing speed; (2) rewrite the proposed changes to not require additional string allocation; > decrease PDF file size when CS are enabled > --- > > Key: FOP-2190 > URL: https://issues.apache.org/jira/browse/FOP-2190 > Project: Fop > Issue Type: Improvement > Components: pdf >Affects Versions: 1.1, trunk >Reporter: Luis Bernardo > Attachments: fop-2190.patch > > > when CS are enabled, the current code may make use of the operators Td and Tj > in situations where TJ would be appropriate leading to an increase in file > size. note: this happens in the PDFPainter.drawText(). -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira
