<p>The way the blockchain is stored on your computer has changed with the latest version.</p>

<p>The developers tweaked it, so that future users can profit from a faster init-proccess.</p>

<p>The new indexing made it necessary to reinitialize your blockchain.</p>

<p>However it should not have taken so long. On my laptop it took about 2 hours. Do you have a very weak computer?</p>

CC BY-SA 3.0
2013-03-27T02:42:43.533Z
I don't think so. It's  MacBook Pro, about 2 years old. Downloading the blockchain also took a long time (about 15 hours).
lurf jurv
CC BY-SA 3.0
2013-03-26T14:41:48.380Z
2013-03-26T14:41:48.380Z
Gundon
<p>0.8x versions of the bitcoin-qt client now use a different database to store the blockchain.  This change was necessary to allow for larger block sizes.</p>

<p>The reindexing process is converting the previous database (which used BerkleyDB) into the new one (Which uses LevelDB).</p>

CC BY-SA 3.0
2013-03-27T02:43:09.253Z
Okay, but how come it had to do it again? It said something about a "Corrupted database".
lurf jurv
CC BY-SA 3.0
2013-03-27T04:40:26.293Z
@lurfjurv - Either something went wrong during the reindexing or your current copy of the old-DB blockchain is corrupted.  If it blows up the same way again, your best option would be to blow away the blockchain and redownload it from scratch.
Compro01
CC BY-SA 3.0
2013-03-28T14:35:20.637Z
Thanks, although I would like to avoid redownloading if at all possible; it took about 48 hours the first time.
lurf jurv
CC BY-SA 3.0
2013-03-28T14:40:31.423Z
@lurfjurv - As opposed to the ~96 hours you just waited for it to attempt to reindex?
Compro01
CC BY-SA 3.0
2013-05-03T13:41:36.673Z
Oh, I wasn't running the reindex all the time. It probably took about 10 hours total, just when my computer was open.
lurf jurv
CC BY-SA 3.0
2013-03-26T18:15:33.220Z
2013-03-26T18:15:33.220Z
Compro01
<p>When I upgraded to 0.8.1, it said Reindexing blocks on disk and it took about four days (Grr).  But later, it said something about a corrupted database and it had to do it again! What is it doing?</p>

<bitcoin-core>
What does "Reindexing blocks on disk" mean?
lurf jurv
# What does "Reindexing blocks on disk" mean?

(Asked by: username_0 on 2013-03-26)

When I upgraded to 0.8.1, it said Reindexing blocks on disk and it took about four days (Grr). But later, it said something about a corrupted database and it had to do it again! What is it doing?

**Tags:** bitcoin-core


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## 2 answers

### Answer by username_2 on 2013-03-26. Score: 5 | Accepted answer

0.8x versions of the bitcoin-qt client now use a different database to store the blockchain. This change was necessary to allow for larger block sizes.

The reindexing process is converting the previous database (which used BerkleyDB) into the new one (Which uses LevelDB).

> **Comments:**
> **username_0**: Okay, but how come it had to do it again? It said something about a "Corrupted database".  
> **username_2**: @lurfjurv - Either something went wrong during the reindexing or your current copy of the old-DB blockchain is corrupted.  If it blows up the same way again, your best option would be to blow away the blockchain and redownload it from scratch.  
> **username_0**: Thanks, although I would like to avoid redownloading if at all possible; it took about 48 hours the first time.  
> **username_2**: @lurfjurv - As opposed to the ~96 hours you just waited for it to attempt to reindex?  
> **username_0**: Oh, I wasn't running the reindex all the time. It probably took about 10 hours total, just when my computer was open.  

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### Answer by username_1 on 2013-03-26. Score: 0

The way the blockchain is stored on your computer has changed with the latest version.

The developers tweaked it, so that future users can profit from a faster init-proccess.

The new indexing made it necessary to reinitialize your blockchain.

However it should not have taken so long. On my laptop it took about 2 hours. Do you have a very weak computer?

> **Comments:**
> **username_0**: I don't think so. It's  MacBook Pro, about 2 years old. Downloading the blockchain also took a long time (about 15 hours).  

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