[
https://issues.apache.org/jira/browse/PDFBOX-4883?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17148853#comment-17148853
]
Alfred commented on PDFBOX-4883:
--------------------------------
I've profiled the new code and it looks good.
Before the change, BigDecimal.floatValue(String) was taking 8 times more than
all the matrix multiplications performed to parse a PDF.
Now I only see Float.valueOf(String), which takes half the time needed by the
matrix multiplications.
Who knew BigDecimal was so slow ...
> COSFloat is extremely slow
> --------------------------
>
> Key: PDFBOX-4883
> URL: https://issues.apache.org/jira/browse/PDFBOX-4883
> Project: PDFBox
> Issue Type: Bug
> Components: PDModel
> Affects Versions: 2.0.20, 3.0.0 PDFBox
> Reporter: Alfred
> Assignee: Andreas Lehmkühler
> Priority: Major
> Labels: display, optimization, parsing, textextraction
> Fix For: 3.0.0 PDFBox
>
> Attachments: After.png, Before.png, PDFBOX-4883-b.patch,
> PDFBOX-4883.patch, extreme-values-out.pdf
>
>
> I am testing text extraction from PDF and profiling the execution.
> I found that biggest time consumer is the COSFloat class.
>
> All other improvements I suggested so far are small compared to this.
> But this is the also the most complex one.
>
> I have attached te profiler output for the same text extraction, with and
> without the COSFloat changes.
> The time to extract the same text was 4 times long with the original COSFlow,
> because of its use of BigDecimal.
> I will try to write extra tests for all cases I see in the original COSFLoat
> code, if they are not already tested.
> Then I will submit for review a new COSFloat version.
>
> I think this affects parsing and displaying PDFs too, not just text
> extraction.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
