bitcoin main window takes a long time (20 minutes+) to appear #540

When I start bitcoin, it takes a very long time for the main window to appear. About 10-30 minutes. The following is added to ~/.bitcoin/debug.log when bitcoin is started, and nothing more appears until the main window appears:

Bitcoin version 0.4.0-beta
OS version Linux 2.6.38-11-generic x86_64
System default language is 66 en_DK.UTF-8
Language file locale/en_DK/LC_MESSAGES/bitcoin.mo (English (Denmark))
Default data directory /home/rune/.bitcoin
Bound to port 8333
Loading addresses...
dbenv.open strLogDir=/home/rune/.bitcoin/database strErrorFile=/home/rune/.bitcoin/db.log

After the main window appears, the following information is added to debug.log

Loaded 249074 addresses
 addresses            627873ms
Loading block index...
LoadBlockIndex(): hashBestChain=000000000000077a9c9a  height=147002
 block index          436502ms
Loading wallet...
nFileVersion = 40000
fGenerateBitcoins = 0
nTransactionFee = 1000000
fMinimizeToTray = 0
fMinimizeOnClose = 0
fUseProxy = 0
addrProxy = 127.0.0.1:9050
fUseUPnP = 1
 wallet                  435ms
Rescanning last 106 blocks (from block 146896)...
 rescan                 5251ms
Done loading
mapBlockIndex.size() = 147005

As a first measure you could delete addr.dat from your bitcoin folder. This is completely safe and should improve startup time a lot.

What kind of hardware are you running it on? Either your CPU or disk is a little slow.

I deleted addr.dat, this is the output now:

Bitcoin version 0.4.0-beta
OS version Linux 2.6.38-11-generic x86_64
System default language is 66 en_DK.UTF-8
Language file locale/en_DK/LC_MESSAGES/bitcoin.mo (English (Denmark))
Default data directory /home/rune/.bitcoin
Bound to port 8333
Loading addresses...
dbenv.open strLogDir=/home/rune/.bitcoin/database strErrorFile=/home/rune/.bitcoin/db.log
Loaded 0 addresses
 addresses               190ms
Loading block index...
LoadBlockIndex(): hashBestChain=000000000000085dbedd  height=147225
 block index          443179ms
Loading wallet...
nFileVersion = 40000
fGenerateBitcoins = 0
nTransactionFee = 1000000
fMinimizeToTray = 0
fMinimizeOnClose = 0
fUseProxy = 0
addrProxy = 127.0.0.1:9050
fUseUPnP = 1
 wallet                  118ms
Done loading
mapBlockIndex.size() = 147228
nBestHeight = 147225
setKeyPool.size() = 100
mapWallet.size() = 2
mapAddressBook.size() = 4

I have an Intel Q9550 CPU (four cores, downclocked to 2 GHz) and my home folder is on an Intel X-25M SSD. This was never a problem with versions before 0.4, the main window appeared instantly back then. blkindex.dat is 254.7 MB in size.

I believe this has been fixed with the QT implementation - load times are now much shorter.

I dont think load times have changed with QT as the load methods in AppInit2 haven't changed. This issue appears to be specifically about slow load times loading the block index, which should effect both bitcoind and bitcoin-qt.
Since no developer (AFAIK) can reproduce this error, is there any way the original reporter can profile bitcoin while it is loading?

This bug is now gone for me. I believe the cause was an SSD drive that had slowed down. The read speeds had dropped to ~700KB/s which corresponds to about 15 minutes to read the 600MB block chain file. After the read speed have returned to normal this issue is no longer present; loading takes 15 seconds now.

I do still think 15 seconds to load the GUI is a long time, though. Perhaps it would be a good idea display the GUI as soon as the bitcoin process is started, and not wait until the block chain has been read from the hard drive? The GUI could say "Loading block chain from disk: 3%..." while reading the data, so as to let the user know that everything is working, it's just a slow storage medium that is causing the wait.

Actually the new qt gui does just that.

runeksvendsen reply@reply.github.com wrote:

This bug is now gone for me. I believe the cause was an SSD drive that had slowed down. The read speeds had dropped to ~700KB/s which corresponds to about 15 minutes to read the 600MB block chain file. After the read speed have returned to normal this issue is no longer present; loading takes 15 seconds now.

I do still think 15 seconds to load the GUI is a long time, though. Perhaps it would be a good idea display the GUI as soon as the bitcoin process is started, and not wait until the block chain has been read from the hard drive? The GUI could say "Loading block chain from disk: 3%..." while reading the data, so as to let the user know that everything is working, it's just a slow storage medium that is causing the wait.

Reply to this email directly or view it on GitHub: #540 (comment)

Excellent. I just built bitcoin-qt, looks very nice!

In my case, it's very slow too. And each time I start bitcoin-qt, it take more time to load the entire application than the previous one.