When reorgs greater than 6 are detected we refrain from taking
action (rolling back the chain) and wait for either user interaction
or till the chain extends the chain-tip again.
The current system writes based on the amount of changes, which is a bit
risky as long as we have small blocks as the amount of changes may for
hours be below the "lets write" limit.
So also write every 5 minutes, just to make sure we won't keep data in
memory longer than needed. Also this allows pruning to happen for people
that don't run their node all the time.
we only save a subsection of stuff in memory on each round of saving,
but I set the counter to zero on how long to wait for the next save.
This makes us save more often till we actually saved most stuff, avoiding
buildups of caches until we do the periodic big flush.
This change makes the limits be static variables, which means they are
only settable once for a process. The only usecase so far is to use much
smaller limits in testing situations.
This allows queries like RPC and mempool-accept to continue
even during a prune (we just use the 'old' DB) and when its
done the last active query will delete the old DB.
This assumes a sane filesystem where you can rename a file that
is in use.
On all mature operating systems and filesystems creation of a 1GB file
will not actually use that data, only when we start using blocks does
the disk space get used.
As such this is a premature optimization that Core added and I ported to
Flowee which this commit removes.
Additionally, increase the block file size to 1GiB
Instead of having a magic 10 open files, we now have a scheduled
run that closes all mapped files 30 seconds after last usage.
This allows many files to be opened with extremely low overhead and
cost (they are not actually loaded until needed, and even then only
per 4K page).
We inherited the design from Core that you can put in your config
file which chain you will follow (testnet, regtest).
This has the effect that you can't have different config files for
different chains and that we always read the fallback location for
all chains. Especially the last one is just harmful.
So, regtest/testnet can only be selected from commandline.
If you choose one of those, it will look for a flowee.conf in the
related subdir (flowee/regtest/flowee.conf for instance) and NOT
for the global one. The global one is only ever read for mainnet.
TomZ