So we found this problem regarding Delta Update on BW server.
After BW running on production phase for a couple days we saw the update are not running as they should. They’re some extraction that remain on yellow light. It seems like there are no data coming through anymore from ECC to BW side.

It turned out there are a lot of entries Queue-ing on ECC side. Using transaction SMQ1, we could see some entries are waiting in line to be extracted.

It’s like a ‘Clogged Pipes’.
So how do we overcome the clogged pipes? we need to take out the plug.
But, where is the plug in terms of data flow from ECC to BW?

What we don’t know is, there is a difference process to update Full/Initial Datasource and Delta Datasource. Full/Initial data extracted are store in Setup-Table.
If initialization is successfully extracted into BW PSA, delta generated on ECC. From then on, data collection stored in Delta Queue (RSA7) before extracted by Infopackage.

And now for the best part, Unclogging.
It turned out we need to do the V3 job, releasing the entries data delta into queue delta before delta info package is triggered from BW-side.
Go to LBWE.
By clicking the job control and scheduling the job. Data Entries that stuck on SMQ1 are flowing into Delta Queue RSA7.

After setting up the background job process( I think I need to create a blog post on how I do this) for every time delta infopackage requested, the ‘Clogged Pipes’ never seen anymore.