On Tue, Jan 12, 2021 at 8:08 AM Roberto Ragusa <mail@robertoragusa.it> wrote:
On 1/12/21 2:21 PM, Richard Shaw wrote:

> I would think a blockchain is roughly equivalent to a database but I have no idea if the blocks were downloaded in order (appended) or randomly (inserted). The single file (data.mdb) ended up being 96GB in total. It seems to have settled down as I expected but it took about 2 days to download so it was a bit frustrating using my computer at that time. Anything that tried to access /home (my spinning btrfs drive) would basically stall including youtube videos that ran out of cache, browser tabs, etc.
98GB in 48 hours is an average of 500kB/s.
 
A spinning disk can seek 100 time per second, was the filesystem doing a seek every about 5kB of data?
Looks unreasonable, especially since I would not expect the access to be random at all in a blockchain.
Would be interesting to do the same operation in different conditions (SSD <-> HDD, ext4 <-> btrfs).

Yes, I almost stopped and copied the file to somewhere in /var since my system SSD (970 EVO m.2) is still EXT4. To be fair, it seemed to save up the download for some time and then dump to the disk all at once. My system wasn't unuseable all the time, but during the writes to disk it was very frustrating. 

I knew it wasn't an overall system problem since glances showed low CPU and memory usage. It's a Ryzen 5 3600 w/ 32GB of memory :)

Thanks,
Richard