Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On 10.06.2013 13:46, Lutz Vieweg wrote: >> I wonder why the peer has smaller max bio size in the first place, >> though. > > Because the harddisk in the peer is connected to a 3ware/LSI 9750 > controller > which supports a max_hw_sectors_kb size of 128, only - while the harddisk > in the primary is connected to an on-board controller supporting much > larger > values. > > (BTW: The 3ware/LSI raid controllers perform incredibly bad when used with > fast SSDs due to this ridiculously low max_hw_sectors_kb - it seems they > try > to promote their overpriced "SSD support" add-on-dongle that way. I can > only > say that I'll never buy a 3ware/LSI controller again, because of that.) Btw: You can change that on LSI MegaRAID controllers. My dear friends from Thomas-Krenn.AG have written it into their wiki: http://www.thomas-krenn.com/de/wiki/Max-hw-sectors-kb_bei_LSI_Controllern_anpassen (Sorry, the explanation is German but the rest is in English. You're from Germany anyway.). They are translating their wiki gradually into English. The driver megaraid_sas has a module parameter "max_sectors". Cheers, Sebastian