Mutation hangs forever

Users Dgraph
1

My dgraph installation is on a single host machine. I am having an issue with dgraph mutation queries. Under a high throughput after couple hundred mutations with CommitNow, the mutation query hangs (unless I use context timeout) forever, and the same connection doesn’t work anymore.

I have seen this behavior when I use commitNow with mutation. With --ludicrous-mode or removing the commitNow flag, I don’t see the connection issue.

Info about my installation and environment:

Dgraph Version: 20.11.1
Dgraph go clients:
github.com/dgraph-io/dgo/v200

grpc client:
google.golang.org/grpc

P.S. I am new to this forum and had created this topic earlier under tag Users. No one seems to have responded to that one, hence I was wondering It could be because of an incorrect tag.

2

Hi @bnarang ,
Dgraph performs checks and aborts concurrent mutations on the same attribute/edge. Please see this video for some background.

As the number of concurrent mutations increase, the overhead on Dgraph to check for transaction aborts increases. You can take a CPU profile from alpha and zero when the mutations are hanging and share with us. It may reveal what exactly Dgraph is doing.