pdf width and height scales differently as snapshot

• Puppeteer version: 1.10.0
• Platform / OS version: mac HighSierra 10.13.4
• URLs (if applicable):
• Node.js version: v7.6.0

What steps will reproduce the problem?

const puppeteer = require('puppeteer');
const args = process.argv;
var browser;
var page;

(async() => {
	try{
	    pageWidth = 800;
	    pageHeight = 990;
	    
	    browser = await puppeteer.launch({timeout:0,args: ['--no-sandbox', '--disable-setuid-sandbox','-disable-web-security']});
	    page = await browser.newPage();					    
	    await page.setViewport({width:pageWidth, height:pageHeight});
	    await page.goto("file:" + args[3], { timeout: 0, waitUntil: 'networkidle0' });
						
	    await page.screenshot({path: '_/test.png'});
	    await page.pdf({path: args[4], printBackground: true, width: pageWidth, height:pageHeight});
	}catch(err){
		console.log(err);
	}finally{
		process.exit();
	}
})();`

What is the expected result? The pdf is having page break the same way as the snapshot did, meaning no cutting off of the chart

What happens instead? The width and height of the pdf’s included range seemed to be scaled differently as the snapshot. I was expecting 800 and 990 is about right for a chart to fit in a page, but turns out 800 and 990 means more in pdf than it does in snapshot. The parameter of width and height pass in page.pdf does make a difference, just that there seems to be a scale comparing to how snapshot reacts to viewport size. test.pdf

[phuang0619]

Looks like width and height were scaled to 3/2 times of its passed parameter. In my case In order to get 600 x 440, I have to actually put in width 400 (400 = 600 x 2/3) and height 294 (293.3333 = 440 x 2/3) to get it.

Hopefully, this helps

[poppinlp]

I got this issue too with diff scale. The output pdf size is 750 * 750 when i pass 1000 * 1000 to puppeteer pdf method.