MultiBit got progressively slower after adding more receive addresses

At first, MultiBit was all snappy. Over the course of about 4 weeks I added ~120 more receive addresses. Now, MultiBit is very sluggish, grinding the hard-drive excessively (sometimes for minutes), especially when sending payments or when exiting the program. Today, it displayed a message in the status bar that it couldn't open the wallet and that it will use some rolling backup. After that, it resynchronized for about an hour.

I worry that if things continue this way I will be faced with catastrophic data and money loss.

Do you have any hints on why this might happen or whether I could migrate to another more reliable wallet software which could import all my addresses?

multibit

JPav

Posted 2014-08-18T14:12:10.923

Reputation: 19

I have the same problem. I have only just more than 30 addresses (divided among 17 wallets). The application has literally become unusable, especially when the client sometimes just decides for unknown reason to do a resync for several months back during the startup. The only way I can keep using it is by taking one wallet at time and do transactions - but all wallets loaded at the same time - no way. The I/O gets saturated in only few seconds. I guess I should just take my keys and import them into the good old bitcoin-qt. – None – 2015-05-11T12:48:26.597

Answers

Answering myself.

This seems to be a common problem with MultiBit. The problem however is not with the number of addresses, but with the total number of transactions. They say that because it's a "light wallet", it will not handle a too great total number of transactions.

If I may be allowed the opportunity of a rant, to call on this bullshit. The problem is not with the concept of a light wallet, but with the poor software design of MultiBit (and clones). How can they say that because it's light it can't handle too many transactions? The Bitcoin core client can handle any number of transactions while also acting as a full Bitcoin node and while processing the entire blockchain. The light wallet only skims the blockchain to find transactions referencing the addresses in the wallet, and yet for some reason, because it's light, it can't handle many transactions. Dear MultiBit developers, please get a grip!

UPDATE: You may use the similar light wallet Electrum which does not exhibit this behavior.

JPav

Posted 2014-08-18T14:12:10.923

Reputation: 19

This is a very unproductive rant that I gladly down vote. MultiBit is a great tool that has been developed by users around the world for free and on their free time. If you want a wallet with more functionality simply use something else. – Luca Matteis – 2014-09-08T14:36:46.913

@LucaMatteis I don't think it's unproductive for two main reasons:

It helps people find out the real technical cause why MultiBit becomes unusable after receiving > 200 transactions (which is actually something that most people can reach quite easily)
It reveals the fact that there's no techonological excuse for why a "light wallet" should be unusable for receiving mining revenue or many transactions from any other source

JPav

2014-09-14T18:32:12.000

@LucaMatteis And to comment on the other things you've mentioned: as some poet said, "there's no excuse for bad poetry, because nobody asked you to write it". It is the same with free software. Just because you did it for free (although that's not exactly the case if we add up donations and their plans for cutting their fees from transactions), does not give you the excuse to pump out really bad software that may make the users' life a nightmare and may lead to catastrophic money loss. – JPav – 2014-09-14T18:36:21.250

@LucaMatteis And about getting a wallet with more functionality: I was perfectly happy with MultiBit's lack of functionality, what didn't make me happy was the fact that the program gradually progressed to a state where it was almost unusable and a danger to my funds. – JPav – 2014-09-14T18:38:05.890

It seems very unlikely that a number of addresses as small as 120 could make a significant difference in performance. I would guess there is some other problem that just happens to coincide with you adding addresses.

The inability to open the wallet, and the excessive disk I/O, is particularly troubling. One possible explanation is that the hard drive is failing - the slow I/O being caused by repeatedly retrying failed operations. I would start by backing up all your files and especially your wallet (which you do regularly anyway - right?). If that fails because there are files that the backup software cannot read (without a good reason, e.g. they are locked by another process), or it reports I/O errors, then that would clearly indicate a failing drive that needs to be replaced.

(Generally, if you have good, regular backups of your wallet files, you are fairly well protected against "catastrophic money loss".)

Nate Eldredge

Posted 2014-08-18T14:12:10.923

Reputation: 21 420

I don't believe my hard drive is failing. I'm using it pretty intensively and haven't noticed other similar signs with other programs. (I'm using Ubuntu 14.04 and being a developer myself I would say I'm pretty much a power user.) Also, MultiBit's disk grinding episodes seem to be pretty concentrated around specific actions taken (like sending coins or exiting the program). – JPav – 2014-08-18T15:01:14.877

Also, a S.M.A.R.T. control program also does not indicate any issues with my drive. About the backups, yes I do perform backups pretty often but not after every sending operating and if the program is not very robustly designed I may end up losing all my coins (if for example it creates a new receive address just after my last backup to receive all the change for a small payment). – JPav – 2014-08-18T15:01:55.390

@JPav: Ok, I thought it was worth mentioning since it would need immediate action if true. There are certainly plenty of other wallet programs you could try. As far as backups, many wallet programs maintain a "key pool" where they pre-generate keys, so that, for instance, change addresses are stored and can be backed up well before they are used. I know Bitcoin Core does this; I am not sure about MultiBit as I don't use it. – Nate Eldredge – 2014-08-18T15:14:21.560