Go-ethereum: --fast option seems to override default --syncmode "fast" and put in --syncmode "full" mode

[tonecas]

Please answer these questions before submitting your issue. Thanks!

What did you do?

geth.exe --fast --cache=512 --datadir path/to/datadir --ethash.dagdir path/to/datadir

What did you expect to see?

"Imported new chain segment." messages
no deep validation of blocks.

correct behavior:
geth.exe --syncmode "fast" --cache 512 --datadir path/to/datadir --ethash.dagdir path/to/datadir

What did you see instead?

start getting blocks and checking them.

System details

Version: 1.6.1-stable
Go Version: go1.8.1
OS: windows

[fjl]

I can't reproduce this. It might be that full sync came into effect in some other way, but it's not related to --fast. Closing this because we have plenty of issues about blockchain sync and there is no new info here.

[FredCailloux]

My previous experience seem to corroborate that issue. I've been trying to start a new Ethereum wallet and use geth.exe --fast cache=2048
https://ethereum.stackexchange.com/questions/17136/why-downloading-the-blockchain-with-geth-fast-is-still-very-slow
Every attempt would engage in a very long predicted download time.
After erasing everything and start anew with geth.exe --syncmode "fast" --cache 2048 suddenly I am aiming for a somewhat 2 to 3 hours of download time for the whole blockchain instead of the previous attempts 35 to 45 days predicted.
Big improvement.
More later when I finish the whole implementation process.
geth.exe --syncmode "fast" --cache 2048 seems to do the job pretty well, so far !

[DonRoberto123]

i think u guys could change that, if i put geth.exe --syncmode "fastest" everything jumps by the couple of percentages 3% 5% 7% ... .

and that is every couple of seconds ... .

... just wanted u guys too know, how u can sync the entire chain, in a couple of minutes

[DonRoberto123]

geth syncmode "fastest"

[DonRoberto123]

oooh yeah, u can also add --cache=2048