downloading blocks is too slow

[JimmyGre]

I followed this -- http://linux.ringingliberty.com/bitcoin/ tutorial to install my daemon. But I can not get the bitcoin balance.
I checked here -- https://bitcointalk.org/index.php?topic=595916.0 . It says there are 299134 blocks and would take a day to download. It takes me 2 weeks to download but still less than 290000.
The number of blocks is increasing but really really slow.

Any reasons?

Thank you,
Jim

[Shogen]

It says there are 299134 blocks and would take a day to download. It takes me 2 weeks to download but still less than 290000.
The number of blocks is increasing but really really slow.

The initial sync shouldn't take such a long period of time. Do you have a very limited internet bandwidth?

[JimmyGre]

It says there are 299134 blocks and would take a day to download. It takes me 2 weeks to download but still less than 290000.
The number of blocks is increasing but really really slow.

The initial sync shouldn't take such a long period of time. Do you have a very limited internet bandwidth?

I don't think I have very limited...
it's like adding one block every min....

[cp1]

Is your cpu maxed? It has to process the blocks too.  Low disk space?  Some kind of firewall problem? How many connections do you have?

[21st-century]

You might have poor node connectivity. How many connections do you have? Check that you've setup port forwarding correctly in your router so other nodes can "find" yours easier. Failing that, you can change the source code's outgoing connection # and incoming connection # to be 100 instead of ~8. Improves connectivity and block downloads if you're running a server. Just be careful it doesn't rape your bandwidth.

In future you might want to use a bootstrap.dat. It's a pre-downloaded list of blocks that can vastly speed up how fast you can get a client "up to date." There are some good torrents for this.

[Shogen]

In future you might want to use a bootstrap.dat. It's a pre-downloaded list of blocks that can vastly speed up how fast you can get a client "up to date." There are some good torrents for this.

The link to the bootstrap torrent can be found directly on bitcoin.org download page. https://bitcoin.org/en/download

If you know how to download a torrent file, you can speed up this process by putting bootstrap.dat (a previous copy of the block chain) in the Bitcoin Core data directory before starting the software.

[JimmyGre]

In future you might want to use a bootstrap.dat. It's a pre-downloaded list of blocks that can vastly speed up how fast you can get a client "up to date." There are some good torrents for this.

The link to the bootstrap torrent can be found directly on bitcoin.org download page. https://bitcoin.org/en/download

If you know how to download a torrent file, you can speed up this process by putting bootstrap.dat (a previous copy of the block chain) in the Bitcoin Core data directory before starting the software.

Sorry, really new for bitcoin. How can I do that on CentOS server?
Many many thanks~
J

[grue]

You might have poor node connectivity. How many connections do you have? Check that you've setup port forwarding correctly in your router so other nodes can "find" yours easier. Failing that, you can change the source code's outgoing connection # and incoming connection # to be 100 instead of ~8. Improves connectivity and block downloads if you're running a server. Just be careful it doesn't rape your bandwidth.

this is bullshit. bitcoin core only downloads from one peer at a time. having more peers does not improve download speed.

[cp1]

You'll have to install a torrent client, like transmission.

[cahirlet]

Mine took a few days. If you want it to be faster, download the bootstrap from the official site.
Go to https://bitcoin.org/en/download this and scroll to the bottom.
The QT will verify the blocks when starting up. If you do not want to download the blocks, try a light weight client like multibit 

[JimmyGre]

Mine took a few days. If you want it to be faster, download the bootstrap from the official site.
Go to https://bitcoin.org/en/download this and scroll to the bottom.
The QT will verify the blocks when starting up. If you do not want to download the blocks, try a light weight client like multibit 

Thank you Cahirlet. I'm not sure where I should put the bootstrap.dat.torrent file. under /root/bitcoin I have .git; contrib; doc; qa; share; src folders. Which one should contain bootstrap? And to start this bootstrap, can i just run '$bitcoin = new jsonRPCClient('http://admin:password@127.0.0.1:8332/');' ?

Many many thanks,
J

[cahirlet]

Mine took a few days. If you want it to be faster, download the bootstrap from the official site.
Go to https://bitcoin.org/en/download this and scroll to the bottom.
The QT will verify the blocks when starting up. If you do not want to download the blocks, try a light weight client like multibit 

Thank you Cahirlet. I'm not sure where I should put the bootstrap.dat.torrent file. under /root/bitcoin I have .git; contrib; doc; qa; share; src folders. Which one should contain bootstrap? And to start this bootstrap, can i just run '$bitcoin = new jsonRPCClient('http://admin:password@127.0.0.1:8332/');' ?

Many many thanks,
J

Note: You need to use torrent client in order to get the blockchain file. Try using a torrent client. As to how to import it, navigate to ~/.bitcoin/ and paste your bootstrap.dat or any other name that u have finished torrenting. Personally I like this: http://www.utorrent.com/downloads/linux
Wish you good luck!

[JimmyGre]

Mine took a few days. If you want it to be faster, download the bootstrap from the official site.
Go to https://bitcoin.org/en/download this and scroll to the bottom.
The QT will verify the blocks when starting up. If you do not want to download the blocks, try a light weight client like multibit 

Thank you Cahirlet. I'm not sure where I should put the bootstrap.dat.torrent file. under /root/bitcoin I have .git; contrib; doc; qa; share; src folders. Which one should contain bootstrap? And to start this bootstrap, can i just run '$bitcoin = new jsonRPCClient('http://admin:password@127.0.0.1:8332/');' ?

Many many thanks,
J

Note: You need to use torrent client in order to get the blockchain file. Try using a torrent client. As to how to import it, navigate to ~/.bitcoin/ and paste your bootstrap.dat or any other name that u have finished torrenting. Personally I like this: http://www.utorrent.com/downloads/linux
Wish you good luck!

Cool~ Thank you!!!

[Cryddit]

Actually a high latency, or a slow computer, can cause very slow downloads in the bitcoin blockchain, even if you have good bandwidth.

The way the initial block download works, your client goes and asks somebody, "what's the current block", and they say, BLOCK ID XXXXX.  And then since you don't have XXXXX, you ask them for that and they send it to you, but after you download it, then you look at its block header and discover that the previous block was WWWWW - and you don' t have that one either!  So you ask, "Hey could you give me  a copy of Block WWWWW?"  And they send that, and you look at it, and its parent was VVVVVV, and you don' t have that either, so you ask.....  and so on, back to the Genesis block.

The deal here is that you don't know which additional block you need next (and therefore can't ask for it) until you've gotten the current block, so you can only have one request for a block out there at a time.  If you have a high latency, or the peer you asked the block for has a high latency, it can take a few seconds to get each and every block, even if you both support very high transfer rates.

Then there's a CPU bottleneck to worry about.  Your peer does all kinds of cryptographic checks on each downloaded block, so if your CPU is slow, that may even dominate the latency time. 

It's worthwhile to get the bitcoin blockchain using bittorrent; with the bittorrent protocol at least you can have requests out there and active for more than one block at a time. 

[softtissue]

Trying to use SSD, it will improve the download speed obviously.

[cahirlet]

Trying to use SSD, it will improve the download speed obviously.

Verification and write speed, after downloading, your computer need to verify the blocks individually. SSD greatly improves the speed. Download speed is dependent on your internet speed, not on hardware. 

[swapcoiner]

Check your network bandwidth. Block downloads depends on network speed.

[zvs]

Use

bitcoin-qt (or bitcoind) --maxconnections=1 --connect=5.9.24.81

until you finish syncing the entire blockchain.

This will help w/ two things, 1) you won't use any upstream (& potentially have downstream limited by saturated upstream) by having or connecting to a client that's also downloading the blockchain, 2) you'll receive blocks as fast as your CPU can process them (I have gigabit connection on 5.9.24.81).

[DeathAndTaxes]

Trying to use SSD, it will improve the download speed obviously.

Verification and write speed, after downloading, your computer need to verify the blocks individually. SSD greatly improves the speed. Download speed is dependent on your internet speed, not on hardware. 

Network speed is rarely the bottleneck unless you just have the bad luck of continually connecting to a really slow peer.   Downloading 20 GB @ 5Mbps is only ~8 hours.

Downloading and verification aren't independent steps.  To avoid being spoofed by other nodes your client will download a block, verify it, and then request the next block.  The blockchain is downloaded, verified, and indexed one block at a time.

[Frz]

Are there plans to do block verification (of multiple blocks) in parralel?
Especially during bootstrap.dat loading this would be very useful (because we all have multi core machines) - possibly even utilising the gpu to speed up the process some more.