5G Harq Retransmissions

Question about 5G harq retransmissions.
What is the average number you see in logs?
For example I see minimum 3 and maximum 16 (16 when TB failed to be sent and retransmission occurs at RLC layer).
Distribution is like in attached picture for a log.

image

I think there are a lot of retransmissions and wonder why MCS is so badly chosen.
I thought BLER is 10% for PDSCH/
Anyone facing same issue while analyzing 5G logs?
In the graph is presented “max decoding iterations” ie harq retransmissions (up to 16 retrans per each HARQ process)/

Overlapping may be high on this site from neighbouring sites.

I think it’s not this…
In all logs I checked iterations is at least 3 and max 16.
There are no values like 2 or 1.
But average value looks more like 7-8 iterations, as in the graph above.
And code blocks I see max 24, in DL.
I am amazed but those numbers, as I always thought that IBLER is 10% for PDSCH and HARQ retransmissions is max 1-2 retransmissions, not 7-8 like in the graph.

Which message are you looking in 5G logs to get this?

NR 5G MAC PDSCH STATUS.
Check last IEs, Max decoding Iterations and Total CB Number.

I checked in a 5G SA log file I can see 1, 2, 3 and up to 4 max ReTX.

So you see no values like 16?
Maybe you have 4 max retransmissions for HARQ.
This is a Huawei log, where 16 retransmissions are possible.
Check few tens of them and let me know which is the highest number you found.
Those are HARQ retransmissions not RLC retransmissions.

Checked in NSA log file now, 5 is MAX.

Yes, we can go upto 8 max.

To get a wider view I might need to check the whole db, currently this metric is not loaded.
Both SA and NSA is Nokia.

Is you log for sub-6 NSA?

Yes, it is n78.