What to do with heap?

1

I noticed this morning that my app is having trouble serving static assets. They take forever before finally erroring with ERR_HTTP2_PROTOCOL_ERROR 200 which I found in another issue has something to do with not enough memory for some reason. I noticed my memory usage is extremely high. So I’m trying to investigate that.

image
image1298×824 44.3 KB

@benbjohnson suggested I download a heap of my site in another post for another reason (Site falls over every few hours before rebooting - #32 by benbjohnson). I got the heap, but I have no idea what to do with it. Is there a tool I can use to investigate the heap and see what the memory is being used for?

EDIT: Also it looks like CPU freaked out as well:

image
image1326×828 70.9 KB

(Note I just redeployed so that’s why it dropped at the end there)

2

The heap profile is used with the go command. In addition to Go, it’s useful to have the GraphViz installed too:

$ brew install graphviz

Once that’s all installed, you can run:

$ go tool pprof /path/to/heap

There are a bunch of commands in there but I typically use the "web" command which generates a graph of what the current allocations are:

$ go tool pprof /path/to/heap
Entering interactive mode (type "help" for commands, "o" for options)
(pprof) web

You can also use the "pdf" command which does the same thing but generates a PDF which is easier to share.

You can also just send me the heap profile and I can take a look. :slight_smile:

1 Like