Open mu88 opened 2 months ago
Thank your for your bug report. When running it via VS on Windows, it gave me these results:
The increased heap size, seems to be caused by the System.Text.Json
cache they have internally. I was before noting two things, try to manually install a recent version of System.Text.Json
, it might have some caching fixes included they were doing and the second was that they internally have a timing based cache, which might keep things alive for a few seconds. So GC.Collect()
might help.
Also when doing the following, it seems to not leak for me:
using Microsoft.Playwright;
Console.WriteLine($"Started process under PID {System.Diagnostics.Process.GetCurrentProcess().Id}");
while (true) {
await CreateScreenshotAsync(1920, 1080);
GC.Collect();
Console.WriteLine($"TotalMemory: {GC.GetTotalMemory(false)}");
}
async Task CreateScreenshotAsync(uint width, uint height)
{
using var playwright = await Playwright.CreateAsync();
await using var browser = await playwright.Chromium.LaunchAsync();
var page = await browser.NewPageAsync();
await page.SetViewportSizeAsync((int)width, (int)height);
await page.GotoAsync("https://playwright.dev/dotnet/");
await page.ScreenshotAsync(new PageScreenshotOptions { Path = "Screenshot.png", Type = ScreenshotType.Png });
Console.WriteLine("Screenshot created");
}
Ideally we are able to create a repro without AspNetCore out of it. Do you observe the same without AspNetCore?
Thank you for getting back to me.
Even when adding GC.Collect()
to my ASP.NET Core sample code, the memory slowly increases over time:
However, when running a console app with the following code, I don't see this behavior:
using Microsoft.Playwright;
Console.WriteLine($"Started process under PID {System.Diagnostics.Process.GetCurrentProcess().Id}");
PeriodicTimer timer = new(TimeSpan.FromSeconds(15));
while (await timer.WaitForNextTickAsync(CancellationToken.None))
{
await CreateScreenshotAsync(1920, 1080);
GC.Collect();
Console.WriteLine($"TotalMemory: {GC.GetTotalMemory(false)}");
}
async Task CreateScreenshotAsync(uint width, uint height)
{
using var playwright = await Playwright.CreateAsync();
await using var browser = await playwright.Chromium.LaunchAsync();
var page = await browser.NewPageAsync();
await page.SetViewportSizeAsync((int)width, (int)height);
await page.GotoAsync("https://playwright.dev/dotnet/");
await page.ScreenshotAsync(new PageScreenshotOptions { Path = "Screenshot.png", Type = ScreenshotType.Png });
Console.WriteLine("Screenshot created");
}
In case you're asking why I care: due to the problematic behavior in my ASP.NET Core app (see here) which runs on my Raspberry Pi 4 in a docker compose
stack with a memory resource limit of 1 GB, I see OOM exceptions after some time due to the continuous increasing memory ☹️ I can also configure a memory limit of 0.5 or 2 GB, it doesn't matter: after some time, all the memory is used.
So far, I can only mitigate this by configuring a restart policy for the Docker container, i.e. the process is more or less like this:
So I see the following follow-up questions:
GC.Collect
call be avoided (even though it only seems to slow the memory increase)? Since the .NET garbage collector automatically gets triggered as soon as the memory gets rare, it runs a full GC anyway - but due to the evergrowing unmanaged memory, it cannot reclaim enough memory and the container dies.We are facing the similar problem with this, we are using the asp.net core and we are keeping doing the screenshot. the memory is pretty slow, our service will continue leak and eat up all the 8G memory for 2 days.
@shuowpro: which version of Playwright are you using? I'm now on 1.45.1
and it looks better over the last two weeks:
Before, it was constantly crashing after some days (each color represents a new container):
I'll close it for now, since this issue is unfortunately not actionable for us. It looks like some bug in ASP.NET whereI recommend filing against them. Thanks for your understanding and happy that it seems resolved!
@mxschmitt ...and the ASP.NET Core guys will argue the same: it looks like some bug in Playwright 😥
@mu88 do you have a reference to their response? I hope to dedicate some time to it later this week or reach out to some more experienced .NET experts in that area.
Version
1.45.0
Steps to reproduce
dotnet build
pwsh Web\bin\Debug\net8.0\playwright.ps1 install
dotnet run
)info: NewScreenshotCreator[0] Screenshot created
)Expected behavior
The app should not use more memory over time (both managed and unmanaged).
Actual behavior
The app uses more memory over time (both managed and unmanaged).
Additional context
I quickly analyzed one memory dump. Without further understanding of what's going on in Playwright internally, I don't want to speculate about the unmanaged memory. For the managed memory, however, I already discovered the following:
StdIOTransport
and some reflection code.StdIOTransport
is instantiated inawait Playwright.CreateAsync()
In the following screenshot, you see the increasing memory footprint over time:
In the next screenshot, you see the dominating types retaining the memory (last memory dump taken):
And last but not least, the following screenshot shows several issues, e.g. duplicate strings, sparse arrays, and leaking event handlers:
Environment