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I've been trying to diagnose a message I see in my dmesg output. Last night I was watching a video which really taxed my notebook and I noticed that the computer was super hot and the fan wouldn't stop blasting away at full speed, even after I rebooted. At anyrate, last night and again this morning I am seeing messages withing my dmesg output to the effect of:

EXT4-fs (sda1): re-mounted. Opts: errors=remount-ro,commit=0

and occassionally it'll do a doublt remount with the primary remount listed with commit=600

Now this may be another issue but I thought I might mention it because they could be related, but I am also seeing this message frequently within my output:

composite sync not supported

I looked within syslog to see if I could see any indication of what might be causing this but I see nothing. This seem completely random. Is there something I can do to determine what is causing this?

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It sounds that you have a loose power line or bad battery. The message "...,commit=600" is printed when the notebook is unplugged from a power supply. When reconnecting again, it'll print "...,commit=0". This is a power saving feature, to avoid wasting battery power (but at the expense of data loss on power failure), the filesystem does not immediately write away data.

I don't know what the "composite sync not supported" error is referring to.

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Thank you. I think this just my indeed be the issue since I have recently been having issues with the power supply. – stephen horner Mar 14 '12 at 18:43


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Your answer would be more useful if you summarised some of the information from the link you've posted. As is, it is difficult to know what solution you're suggesting exactly. – James Henstridge Jun 30 '12 at 10:46
While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. – stephenmyall Aug 17 '12 at 20:53

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