kernel: __alloc_pages: 0-order allocation failed.

[steven chang_1]

hello:

I am implementing a very critical system running on redhat 7.1 ,but I found a kernel error message "kernel: __alloc_pages: 0-order allocation failed." . Anybody knows how to solve this problem, patches or other.I check the redhat network, somebody also met the same situation before, but no one could reply this question. I also check the imformation in the internet, and find someone told that it's file
system problem but no solution. If you know how to solve this problem , please tell me .Thank you very much.

steven chang

[Mark Grant · Accepted solution]

This seems to be related to the virtual memory subsystem and you do have choices as to which system you choose. However, that will mean going with one of the trees not supported by Red Hat.

This is what Linus Torvalds has to say about it.

"These are bounce buffer allocations - they do fail, but the failures
should be temporary and the machine should make progress.

There are some nasty issues with HIGHMEM that will be seriously improved
during 2.5.x when we start doing IO directly from highmem for
controllers that can handle it, but that 2.4.x is not likely to really
fix. So you should expect to see messages like the above that are about
"we couldn't allocate memory for bounce buffers", and they _will_ imply
that performance isn't going to be as good as it possibly should be, but
at the same time it shouldn't be a real problem either."

It may get better with an upgrade in the 2.4 series but 2.6 (at all good shops now) seems to be your best bet.