possible speed up for HDDs initial sync, pre-sizing database to the current size of the database instead of constant resizing
So when testing the new 2for1 writes patches on HDDs, I often noticed that I would find monerod stuck. I thought I would dive into the logs for the "time gaps" that would appear. I turned to claude for a [python script to grab these time jumps](https://github.com/Gingeropolous/timejump/tree/main): 

It turns out its LMDB resizing. 

here's an example:

```
2025-02-24 00:33:24.103	[P2P0]	DEBUG	net.cn	src/cryptonote_protocol/cryptonote_protocol_handler.inl:2781	get_next_needed_pruning_stripe: want height 2137588 (2135448 from blockchain, 2137588 from block queue), stripe 2 (10/12 on it and 2 on 3, 0 others) -> 2 (+0), current peers 118? 118? 110 115 115 115 115 115 110 115 115 115
================================================================================ 154.8 seconds 
2025-02-24 00:35:58.868	[P2P7]	INFO	global	src/blockchain_db/lmdb/db_lmdb.cpp:616	LMDB Mapsize increased.  Old: 94870MiB, New: 95894MiB
```

so just grepping and cutting the output file of part of my sync (i was using a high log level, so i don't have the entire sync in logs), i got 2.7 hours of database resizing. 

now, this is where my computer science knowledge limits and understanding of LMDB starts to show, and those that hate AI will want to bludgeon me. But in conversations with claude, it might be that pre-allocating the space on a spinny HDD could reduce fragmentation, placing all the blockchain data closer to each other. But apparently, ext4 should be doing this itself to a degree, but perhaps windows users don't get to experience that. And of course there would be a massive amount of time spent at the beginning of sync allocating 230 GB or whatever. 

This would also cause an immediate failure if the user doesn't have enough space for this initial allocation. Which would be good info for the user, and get them to use --prune mode off the bat, instead of waiting for an error and having to resync because you can't prune an existing when you have no space left. 

anyhoo, just musing about . Perhaps we don't need to worry about spinny HDDs for much longer.... but plenty of folks still have them. 