[GUACAMOLE-1522] Printing is slow for some PDF document

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 1.4.0
• Component/s: guacamole, guacd
• Environment: ubuntu 18.04, GhostScript 9.26 (2018-11-20), Windows Server 2019
• Assignee: Unassigned
• Reporter: Jimmy
• Created: 25/Jan/22 17:49
• Updated: 14/Apr/23 00:33

Description

I attached a PDF document. (Print-Sample.pdf)

This document has 5 pages.

When printing the PDF file on the Apache guacamole, it took more than 30 seconds until the downloading is started.

Once the downloading is started, it's completed in a short time.

As a result of my analysis, the call of read() function takes a long time in the 
guac_rdp_print_job_output_thread() function. (src/protocols/rdp/print-job.c)
 
I captured the print data in the guac_rdp_print_job_write() function and saved them to the files.
I attached some of the print data. (print-001.ps, print-002.ps, print-003.ps)
When I directly use Ghostscript in the terminal to convert them to PDF documents, Ghostscript works quickly.

$ gs -q -dNOPAUSE -dBATCH -dSAFER -dPARANOIDSAFER -sDEVICE=pdfwrite -sOutputFile=print-001.pdf -c .setpdfwrite -f print-001.ps
$ cat print-001.ps print-002.ps > print-002-full.ps
$ gs -q -dNOPAUSE -dBATCH -dSAFER -dPARANOIDSAFER -sDEVICE=pdfwrite -sOutputFile=print-002.pdf -c .setpdfwrite -f print-002-full.ps
$ cat print-002-full.ps print-003.ps > print-003-full.ps
$ gs -q -dNOPAUSE -dBATCH -dSAFER -dPARANOIDSAFER -sDEVICE=pdfwrite -sOutputFile=print-003.pdf -c .setpdfwrite -f print-003-full.ps

 
I hope the Apache Guacamole developer team solves this issue.
Thanks.