Отправлено с iPhone > 2 авг. 2018 г., в 10:02, Qu Wenruo <quwenruo.btrfs@xxxxxxx> написал(а): > > > >> On 2018年08月01日 11:45, MegaBrutal wrote: >> Hi all, >> >> I know it's a decade-old question, but I'd like to hear your thoughts >> of today. By now, I became a heavy BTRFS user. Almost everywhere I use >> BTRFS, except in situations when it is obvious there is no benefit >> (e.g. /var/log, /boot). At home, all my desktop, laptop and server >> computers are mainly running on BTRFS with only a few file systems on >> ext4. I even installed BTRFS in corporate productive systems (in those >> cases, the systems were mainly on ext4; but there were some specific >> file systems those exploited BTRFS features). >> >> But there is still one question that I can't get over: if you store a >> database (e.g. MySQL), would you prefer having a BTRFS volume mounted >> with nodatacow, or would you just simply use ext4? >> >> I know that with nodatacow, I take away most of the benefits of BTRFS >> (those are actually hurting database performance – the exact CoW >> nature that is elsewhere a blessing, with databases it's a drawback). >> But are there any advantages of still sticking to BTRFS for a database >> albeit CoW is disabled, or should I just return to the old and >> reliable ext4 for those applications? > > Since I'm not a expert in database, so I can totally be wrong, but what > about completely disabling database write-ahead-log (WAL), and let > btrfs' data CoW to handle data consistency completely? > This would make content of database after crash completely unpredictable, thus making it impossible to reliably roll back transaction. > If there is some concern about the commit interval, it could be tuned by > commit= mount option. > > It may either lead to super unexpected fast behavior, or some unknown > disaster. (And for latter, we at least could get some interesting > feedback and bugs to fix) > > Thanks, > Qu > >> >> >> Kind regards, >> MegaBrutal >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
