Hi, I'm encountered the following scenario: Several encrypted external USB HDDs were mounted (via a hub) when Something Bad happened: Accidentially the cable connecting the hub to the laptop was disconnected. The devices used at that time were /dev/sda and /dev/sdb. Logfiles showed the usual USB stuff: disconnections, nothing really worrysome, no oops, no bugs. So I almost immediately replugged one drive and mounted it again, the device used was /dev/sdc and performance was as usual. A few minutes later I replugged the other drive and the device it was associated with was /dev/sda. There were no error messages, the mount operation proceeded normally, filesystem recovery went smoothly. The filesystem was not corrupted during normal use afterwards. I don't think the hub is the issue, but the recycling of used /dev/sd* devices: The really strange thing was the considerable loss in performance. Writing files at ~ 1,5 MB/s was about a 10th of the normal throughput. Reading was also slow. I noticed that the drive's LED was blinking slower than usual during drive access, as if there was a delay of ~ 100 ms during write operations. The kernel used was 2.6.21-rc3 with recent loop-aes v 3.1f. I strongly suspect the code of handling SCSI-compatible devices (or whatever the code handling external USB HDDs is called exactly ;-). Earlier kernels (2.6.16.x) just used the next available devices e.g. /dev/sdc & /dev/sdd and did not recycle ones that had been in use already. Is there a way (apart from going back to earlier kernels) to get the old behaviour back? I'd very much like that. A .config option, boot parameter, patch, anything? -- left blank, right bald
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