Messages in this thread | | | Date | Tue, 27 Sep 2011 17:36:49 +0530 | Subject | USB HDD: Write Cache always shown as Disabled | From | Amit Sahrawat <> |
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Why is Write Cache always shown as Disabled (Function: sd_revalidate_disk(), File: drivers/scsi/sd.c) – even though there is write cache in USB HDD and which is enabled. This is verified by enabling/disabling the cached using ‘hdparm’ and then checking the performance.
I have few USB Hard disks – for all of them it is shown to be
Default Message: “Assuming drive cache: Write Through”
If I change the condition in sd_read_cache_type(), if (sdp->skip_ms_page_8){ // goto defaults; } Sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn’t support DPO or FUA.
Can anyone provide any hint to this? Or am I missing something in this?
Thanks & Regards, Amit Sahrawat -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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