Bitcoin Forum

Other => Beginners & Help => Topic started by: MrMushroom on May 18, 2013, 01:14:15 PM



Title: Blockchain Download/Update With Any Coin Constant Hard Drive Thrashing Question?
Post by: MrMushroom on May 18, 2013, 01:14:15 PM
Hello All,
Just curious as to what exactly is the cause of the excessive Hard Drive Thrashing when downloading or updating any of the Coin Blockchains?
Watching clients update 100 blocks or 1000 of any coin the client just seems to be constantly molesting the Hard drive.
Downloading data or not (When there are blocks left to download) does not make any difference either.
Sometimes they also just stop downloading blocks altogether and get stuck or block numbers go down without any data download.
Any insight appreciated.


Title: Re: Blockchain Download/Update With Any Coin Constant Hard Drive Thrashing Question?
Post by: MrMushroom on May 27, 2013, 08:55:19 AM
 :o

No one has any clue even in this forum?


Title: Re: Blockchain Download/Update With Any Coin Constant Hard Drive Thrashing Question?
Post by: abbyd on May 27, 2013, 09:22:48 AM
Hello All,
Just curious as to what exactly is the cause of the excessive Hard Drive Thrashing when downloading or updating any of the Coin Blockchains?
Watching clients update 100 blocks or 1000 of any coin the client just seems to be constantly molesting the Hard drive.
Downloading data or not (When there are blocks left to download) does not make any difference either.
Sometimes they also just stop downloading blocks altogether and get stuck or block numbers go down without any data download.
Any insight appreciated.


https://bitcointalk.org/index.php?topic=214202.0

The blockchain is huge so you'll need to be patient to download it all. While you download it's also verified.


Title: Re: Blockchain Download/Update With Any Coin Constant Hard Drive Thrashing Question?
Post by: MrMushroom on May 27, 2013, 10:40:58 AM
Thank you for that but that really does not explain why All the Blockchains (Based on P2P correct?) thrash the Hard drive and consume so much CPU time.
Ill use:
http://linuxtracker.org/ (http://linuxtracker.org/)
As an example you can pick pretty much ANY torrent there with equal size to a Coin Block chain it will Download Faster,Thrash a Hard drive less,Not use so much CPU time and still verify every block of data to make sure its not corrupt.
If it really has to verify every single transaction from block zero how is it doing that exactly?
As Stated Ive watched Blockchains download it usually goes:
1.Downloading (Speed Varies) No Update on Block count not going down.
2.Downloading (Speed Varies) Updating. Block count going down.
3.Not Downloading Updating. Block count going down.
4.Not Downloading Not Updating. Block count going not down.
All with 100% CPU usage. Amount of Cores also mean nothing.
Ive Downloaded Blockchains on Single Cores just the same as the Quad core I just used today. That was with ALL 4 cores at 100% usage because of the Bitcoin client.




Title: Re: Blockchain Download/Update With Any Coin Constant Hard Drive Thrashing Question?
Post by: abbyd on May 28, 2013, 06:34:01 AM
Thank you for that but that really does not explain why All the Blockchains (Based on P2P correct?) thrash the Hard drive and consume so much CPU time.
Ill use:
http://linuxtracker.org/ (http://linuxtracker.org/)
As an example you can pick pretty much ANY torrent there with equal size to a Coin Block chain it will Download Faster,Thrash a Hard drive less,Not use so much CPU time and still verify every block of data to make sure its not corrupt.
If it really has to verify every single transaction from block zero how is it doing that exactly?
As Stated Ive watched Blockchains download it usually goes:
1.Downloading (Speed Varies) No Update on Block count not going down.
2.Downloading (Speed Varies) Updating. Block count going down.
3.Not Downloading Updating. Block count going down.
4.Not Downloading Not Updating. Block count going not down.
All with 100% CPU usage. Amount of Cores also mean nothing.
Ive Downloaded Blockchains on Single Cores just the same as the Quad core I just used today. That was with ALL 4 cores at 100% usage because of the Bitcoin client.




OK I don't have an in-depth technical answer for you -  you should probably start reading descriptions of the code architecture (https://bitcointalk.org/index.php?topic=41718.0;all) if you really want to know this.

Put simply: Bitcoin uses a database for the blockchain that requires a lot of I/O to verify transactions. Note that the database recently changed from BerkeleyDB to LevelDB, so the above description will differ slightly in this respect. I can tell you that performance improved about 500% when this change occurred...