[Xapian-discuss] extremely slow merging process

[Vasiliy Sergeev]

Hello everyone,
I have some suspicious slowness with xapian DB workings.
I divided xapian DBs by month to minimize search time and updating DB 
with new data.
But I found that even month DB do not allow to search data very fast as 
it supposed to do.
So I separated last day DB from month DB and update it in real-time 
(with delay 10 secs after each loop).
Idea was in using that last day DB with month DB for search and merge 
last day with month DB at the beginning of every day.
I found that idea here. But that merging process took over 4 hours which 
I suppose extremely slow.
I used xapian-compact utility in this way: xapian-compact monthDB 
lastDayDB updatedMonthDB
Month DB contains about 15M docs (about 60 GB), lastDayDB contains about 
500K docs.
So I had to replacing merging process with updating month DB with the 
same data that I use for last day DB which is not right, I think.
Now I am thinking to divide current month DBinto last day, last week DBs 
because search usually goes about 3 minutes in month DB.
That part I think is very uncomfortable too.
Could anyone give me a hints how to speed up the search and merge 
processes. I have powerful hardware and this still upset me.
I use the same server for search and updating DB since I am limited with 
one server for xapian index.

Thanks,
Vaso.