Bitcoin Forum

So I loaded my bitcoin core wallet on my mac for the first time in months. I can see the 'Overview' Page of my wallet but I cant click into the wallet, it is stuck loading with the Rainbow wheel, and says 'Processing blocks on disk...' in the bottom left corner. It has been stuck like this for a full 24 hours. How do I resolve this issue, thanks.

Your node is either rebuilding your block index or transaction index for some reason. (there's not enough info to tell why)
That's expected to be a slow process but for full 24 hours and counting, your hardware must be old, using external HDD or something since it's even freezing consistently during reindex.

But you can check its progress by checking your "debug.log" file (open with text editor) with the block height of the latest "UpdateTip:" lines.
The file is in your data directory: en.bitcoin.it/wiki/Data_directory#Default_Location (http://en.bitcoin.it/wiki/Data_directory#Default_Location)

For as long as I have been using Bitcoin Core on PC, there has always the problem of the UI being unresponsive when syncing a large number of blocks. I don't know the cause, but it is poor software design. I don't know why it hasn't been fixed, but it has been a problem for a long time so I assume that it will never be fixed.

That's fixable by replacing your RAM and drive or configuring and reducing the dbcache to ensure the RAM won't hit the maximum usage. If you have slow RAM and drive this would cause unresponsive UI even the whole system is stuck because the Bitcoin core is eating many resources including CPU.

Yeah, it's annoying specially if you need to close it.
Had to resort to issuing 'stop' command though bitcoin-cli (with server=1 config) when that was my issue.

In my experience; it's much more severe when I was using an HDD to store the datadir, it's almost unresponsive 99% of the time until it reach the tip.
When I switched to SSD, I noticed that although it freezes when catching up to the tip, it only takes a few second to be responsive again.

FWIW, https://github.com/bitcoin-core/gui/issues/299 (https://github.com/bitcoin-core/gui/issues/299) explain the cause.


Is it that bad? I never had to resort for such thing even though i store everything on HDD.

Well, running a disk-intensive process on an HDD along with code that explicitly hangs the GUI thread is always going to be a recipe for disaster.

Even for a healthy disk, the most reliable ones (I mean the ones you see in data centers from Seagate and WD) would struggle with lots of small reads and writes, which is exactly what the wallet updating code seems to do.

It wasn't that bad, just an annoyance during certain situations while it's syncing and unresponsive.
IIRC, Issuing commands through "bitcoin-cli" while "bitcoin-qt" is unresponsive took longer to return a response.
Of course, shouldn't be an issue if you're using "bitcoind".

For someone (like me) who can't run Bitcoin Core 24/7, I always have to catch-up to the tip at least once a day.
The GUI was almost non-responsive, but only until it fully synced. Not to mention, the time it took was significantly longer than my setup today.
But once it's synced, it rarely freezes.

Never had that issue again since I moved the datadir to an internal SSD.