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Thread-Topic: Getting/Forcing Greater than 4KB Buffer Allocations
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From: "David Christensen" <davidch@broadcom.com>
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Subject: Getting/Forcing Greater than 4KB Buffer Allocations
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I'm investigating a problem with my bce driver which occurs when I ask
for a jumbo
mbuf cluster (through m_cljget()).  When I map the memory for DMA I
normally=20
get 3 memory segments (4KB + 4KB + 1KB) on my system, but on another
user's=20
system he's seeing 2 memory segments (8KB + 1KB).  Is there a
configuration
option that allows this or some other tuning variable involved?  The
system is a=20
Xeon dual-core processor and has 8GB of RAM, running an AMD64 version of
the kernel.
=20
Dave