Unable to parse key: Invalid size for key

[danielmai]

What version of Dgraph are you using?

v20.03.0-beta.20200320 and master

Have you tried reproducing the issue with the latest release?

Haven't tried on the latest release (v1.2.2).

What is the hardware spec (RAM, OS)?

macOS, 16 GB.

Steps to reproduce the issue (command/config used to run Dgraph).

1. Run 1 Zero and 1 Alpha with -v=2 log level.
2. Run some queries and mutations (I used dgraph increment).
3. See this appear in the logs every time there's a tablet size calculation.

I0324 14:46:36.450146    5348 draft.go:819] [0x1] Set Raft progress to index: 40.
I0324 14:48:36.476935    5348 draft.go:1169] Calculating tablet sizes. Found 1 tables
I0324 14:48:36.477004    5348 draft.go:1178] Unable to parse key: Invalid size 25185 for key [33 98 97 100 103 101 114 33 104 101 97 100 255 255 255 255 255 255 255 254]

Expected behaviour and actual result.

The info log showing that a key couldn't be parsed shouldn't happen.

[mangalaman93]

I notice this issue too when I run just docker-compose up in the dgraph folder.
cc: @parasssh @jarifibrahim

[jarifibrahim]

@mangalaman93 @danielmai I tried running dgraph increment and live loader with 1 million dataset on local binary (and docker-compose) but it doesn't show me the error. Any suggestions on what else I can do to reproduce it?

[jarifibrahim]

The key for which dgraph complaints 33 98 97 100 103 101 114 33 104 101 97 100 255 255 255 255 255 255 255 254 is !badger!head key. The first key of table could be badger!head key and dgraph should deal with it accordingly.

The !badger!head key is a special key which helps in case of db crash.

[jarifibrahim]

I could make changes in Badger to not return the !badger!head key but I think dgraph should deal with badger internal keys properly. Badger also had !badger!Move.., !badger!txn, etc keys.

[jarifibrahim]

We decided to keep the code as it is. Nothing needs to be done here. See hypermodeinc/badger#1309 (review)