Huge difference between ASC and DESC ordering

I have the following query

which takes 90 seconds to finish. *JOB_MEMORY* has 45 million rows,
*JOB_MEMORY_STORAGE* has 50 000 rows.

Query plan:

As you can see, it is indeed using an index *JOB_MEMORY_id_desc* in a
backward direction, but it is very slow.

When I change ordering to *desc* in the query, the query finishes
immediately and the query plan is

There is also an index on *JOB_MEMORY.id*. I also tried a composite index on
*(fk_id_storage, id)*, but it did not help (and was not actually used).
I ran *ANALYZE* on both tables.

Postgres 9.6.2, Ubuntu 14.04, 192 GB RAM, SSD, shared_buffers = 8196 MB.
How can I help Postgres execute the query with *asc* ordering as fast as the
one with *desc*?

Thank you.

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