1TB micro SD card for storing blockchain, any reason not to do this?

[zabzob]

Hey all, the 1TB SSD on my Thinkpad T590 (running a full node) is running out of space and the blockchain will outgrow it within the next few months. Because of current high SSD prices, I'm looking for a cheaper alternative to upgrading to a 2TB SSD. Since the laptop has an SD card reader, I'm wondering whether storing the blockchain on a 1TB microSD card would create any issues?

[LoyceV]

I expect this to work fine. But: only put blocks on the SD card, not chainstate! Depending on your RAM, Bitcoin Core will write terabytes of data to chainstate, and SD cards don't handle that very well. The blocks directory is written only once.

[zabzob]

I expect this to work fine. But: only put blocks on the SD card, not chainstate! Depending on your RAM, Bitcoin Core will write terabytes of data to chainstate, and SD cards don't handle that very well. The blocks directory is written only once.

Thanks so much, I'll do it this way

[nc50lc]

Thanks so much, I'll do it this way

I take that you're already aware that it requires --blocksdir arg or config to tell Core where the new blocks directory path is?
If not, I recommend setting it in your bitcoin.conf file.

Anyways, what happened to your other option which is HDD? It can be plugged externally.
I saw you mentioned this in your other reply a few months ago.

[zabzob]

I take that you're already aware that it requires --blocksdir arg or config to tell Core where the new blocks directory path is?
If not, I recommend setting it in your bitcoin.conf file.

I wasn't aware of this, but was going to try to figure it out or ask here once I have the sd card. Thanks for saving me the trouble, I'll edit the config file as you explain when the time comes. It will probably be a month or two before I migrate the blocks file.

Anyways, what happened to your other option which is HDD? It can be plugged externally.
I saw you mentioned this in your other reply a few months ago.

I considered this option, but would rather avoid using an external device, since the laptop moves around frequently. I would have gone this way had the sd option not been feasible. I might still do it if an external hdd is much cheaper than a 1tb sd card. There's a relatively cheap sd from Sabrent that looks reliable.

[LoyceV]

I take that you're already aware that it requires --blocksdir arg or config to tell Core where the new blocks directory path is?

I prefer to deal with this on a filesystem level (on Linux), so I just use a symlink as blocks directory. Or you can just mount the SD card as blocks directory directly.

[zabzob]

I take that you're already aware that it requires --blocksdir arg or config to tell Core where the new blocks directory path is?

I prefer to deal with this on a filesystem level (on Linux), so I just use a symlink as blocks directory. Or you can just mount the SD card as blocks directory directly.

Thanks, I'll consider this option as well

[Bitcoin Smith]

SD card slots are available in the old model laptops, and I assume their R/W speed is less compared to SSD or even HDD!

Why not just use an HDD that is reliable compared to an SD, but you said Micro SD, which is even possible to insert in a laptop without the SD card reader? That is going to take months to complete sync.

[nc50lc]

Why not just use an HDD that is reliable compared to an SD, but you said Micro SD, which is even possible to insert in a laptop without the SD card reader? That is going to take months to complete sync.

This is why it's only the blocksdir that'll be moved out of the internal SSD.
And T590 has an integrated SD Card reader, it's an SD Card slot on its side.

If it's about sync speed, OP obviously already has his node synced based from the post's context,
it's just he needs to upgrade his 1TB SSD since it wont have enough space for the blockchain a few years from now.
The main issue is if he'll need to rescan or build other databases which will be slower than HDD.

I take that you're already aware that it requires --blocksdir arg or config to tell Core where the new blocks directory path is?

I prefer to deal with this on a filesystem level (on Linux), so I just use a symlink as blocks directory. Or you can just mount the SD card as blocks directory directly.

Personally, I prefer the native way of how Bitcoin Core manages its directories.

[LoyceV]

SD card slots are available in the old model laptops, and I assume their R/W speed is less compared to SSD or even HDD!

Some SD cards are faster than some HDDs, but none of that matters much for one-time writing.

Why not just use an HDD that is reliable compared to an SD

Why are you asking things OP already answered?

I considered this option, but would rather avoid using an external device

but you said Micro SD, which is even possible to insert in a laptop without the SD card reader?

That completely depends on the laptop, I've seen them with all kinds of slots.

That is going to take months to complete sync.

With the right hardware, it can be done within a day.

The main issue is if he'll need to rescan or build other databases which will be slower than HDD.

For raw read speed, I wouldn't be surprised if a (quality) SD card is faster than an equal size HDD. Those disks are limited by their spinning speed, my 2 TB 2.5" laptop drive doesn't get above 100 MB/s.

Personally, I prefer the native way of how Bitcoin Core manages its directories.

The main reason I don't do that, is laziness Creating a symlink is faster than reading application-specific documentation.

[ABCbits]

OP, have you checked average cost of 2TB microSD and 2TB SSD on place where you live? Both of them share some same component, so i notice price of both SD and microSD card have risen a lot in past year. If the price gap is relative small, replacing your internal SSD with 2TB ones probably makes more sense.

but you said Micro SD, which is even possible to insert in a laptop without the SD card reader?

Since OP mentioned type of his laptop, it would be great if you checked specification of that laptop before writing your reply.

Despite the redesign, the port selection has not changed significantly compared with the Lenovo ThinkPad T580. The full-size SD card-slot has been removed in favor of a microSD slot.