Bitcoin Forum

For a few days now, I've noticed that every time I start the Bitcoin client, it goes nuts on disk usage for about 5 minutes and then quiets down.  I finally got curious enough to find out what was going on, and it turns out that I get a large burst of disk activity every time a line "AddAddress(...)" appears in debug.log.  Tracking this down, it seems to boil down to this offending line in net.cpp:

429: bool AddAddress(CAddress addr, int64 nTimePenalty)
430: {
...
444:              CAddrDB().WriteAddress(addr);
...
470: }

So what's going on is that every time there's a new address, the address database is opened, a new record is stored, and then the database is closed (and presumably flushed to disk).  This last part is what I think is driving BDB nuts writing stuff out.

Would it be too hard to keep a single CAddrDB object floating around (maybe lock it with a CRITICAL_SECTION), open it once on startup and close it once on shutdown?  Addresses are volatile information that doesn't need to be stored *right this minute* or bitcoin will fail.  They can be recreated by polling peers if need be after a crash.  The code should reflect this lack of urgency to store addresses, and doing so will substantially reduce the disk usage on Bitcoin startup.

You're right, patches would be welcome. Also see the bitcoin-development mailing list.

Thanks for the heads up about the mailing list.  I'll try to put a patch together soon.

Please also consider the file fragmentation isssue. A brand new blockchain database will split in over 15000 fragments all over the disk.