# Sumatra PDF is a PDF, ePub, MOBI, CHM, XPS, DjVu, CBZ, CBR reader for Windows

We stress test Sumatra to ensure it doesn't crash. Stress testing on my collection of documents is part of release process.
A simple stress test: run `SumatraPDF.exe -console -n 2 -rand -stress-test ${dir}` It'll scan a given directory, randomize order of files and render every known document type.
Stress test can be customized with the following cmd-line options:

- `-stress-test foo.pdf 8x` : render only foo.pdf, do it 8 times
- `-stress-test z:\` : render all documents in z:\ directory
- `-stress-test y:\testdocs *.pdf;*.xps 2x` : render only .pdf and .xps document in y:\testdocs directory, render each document twice
- `-n ${parallelCount}` : number of documents to test in parallel
- `-rand` : randomize order of files. Also distributes equally among different file types (helps to test different formats equally as opposed to reading sequentially, which can spend a lot of time testing *pdf files, then a lot of time testing .cbz files etc.)
- `-console` : show console so that we can see progress

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