Meaning of だけは in the sense of "to do all that one can"

Question

I have several sentences where だけは is translated as "to do all that one can".

覚えるだけは覚えたのだから、後は試験の日を待つだけだ。
I’ve remembered everything I could, so now all I have to do is wait for the day of the test to come.

指示のとおりにやるだけはやったが、いい結果が出るかどうか自信がない。
I followed the instruction and did all that I could, but I have no confidence that I’ll have good results.

恋愛のことは両親にも話すだけは話しました。
I told my parents everything about my love life.

Is it a special pattern or is it explicable with the "usual" meaning of だけ? Can it be decomposed so that I can understand where だけは translated as "to do all that one can" comes from ?

Thanks

Answer 1

Is it a special pattern or is it explicable with the "usual" meaning of だけ?

It's meaning (2) in this definition. In this case, dake corresponds to an upper limit or the maximum possible. In English "only" usually implies a limitation or a lack but in Japanese "dake" can also imply exactitude, something like "precisely", or up to some limit or another.

覚えるだけは覚えたのだから、後は試験の日を待つだけだ。

I’ve remembered everything I could, so now all I have to do is wait for the day of the test to come.

Not a good translation of 覚える, "remembered" should be "learned" or "memorised". Anyway here it means "I've learned to the limit of my capacity".

指示のとおりにやるだけはやったが、いい結果が出るかどうか自信がない。

I followed the instruction and did all that I could, but I have no confidence that I’ll have good results.

Yes, here again it is the upper limit.