On 30/07/12 13:33, Michael Brunnbauer wrote:
Hello Andy,
On Sun, Jul 29, 2012 at 05:22:57PM +0100, Andy Seaborne wrote:
How big are the node* files (node2id.dat, .idn, nodes.dat) in the
resulting database in this case?
node2id.dat 9470738432 bytes
9,470,738,432 => 9G
node2id.idn 50331648 bytes
50,331,648 => 50M
Much less than RAM size.
nodes.dat 20182577027 bytes
This file is written sequentially and isn't read during loading so
should not be an issue.
In 64 bit mode, the B+Tree node2id is a memory mapped file and the OS
takes care of paging+caching the data.
I think that use of
JVM_ARGS="-Xmx32768M -server"
is in fact making things worse: the heap grows to 32G, reducing the
space available to the OS for mmap files. So it is squeezing out the OS
managed mmap files and the result is that there is little real RAM
devoted to caching the node table.
2G heap should be enough IIRC (caveat long literals).
Andy
Regards,
Michael Brunnbauer
