The slow usb-storage performance is still valid in Kubuntu 9.10 (linux-image-2.6.31-14-generic). It was important for me to format my SDHC card (16 GB Class 10!) with a non journaling filesystem. I've tried
I've tried several card readers which have slighty different performance but they have in general the same problem. ID 05ca:1880 Ricoh Co., Ltd ID 05e3:070e Genesys Logic, Inc. X-PRO CR20xA USB 2.0 Internal Card Reader ID 05e3:0715 Genesys Logic, Inc. USB 2.0 microSD Reader (labeled as Hama 6 in 1) ID 05e3:0715 Genesys Logic, Inc. USB 2.0 microSD Reader (labeled as Sandisk Micromate) I have tried adding mount options like async, noatime, nodiratime or all at once. I guess the module needs to "deparallize" or "sequentialize" i/o transactions. Problems arise when processes like updatedb, firefox cache writes, ldconfig, update mandbare running. These processes run at 10 - 110 kb/sec instead of 10 mb. Booting seems to be almost read only and speed is fast. But when I tried to write a big iso image onto the SDHC card it was running with 400 - 800 kb/sec. It became amazingly fast when I entered sync. Then I had between 6 and 14 mb/sec for the rest of the iso image. I hope someone can write a scheduler for this stupid devices which don't have a high performance i/o-controller. This would really improve my experience with beta distributions on my laptop which doesn't have a 2nd harddrive. -- Low performance on usb-media and DVD-RAM in sync mode https://bugs.launchpad.net/bugs/19982 You received this bug notification because you are a member of Ubuntu Bugs, which is a direct subscriber. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
