Hi Coiby,
much better. Thanks!
Personally would also mention our recommended default value as that would emphasize on how significantly the size gets underestimated. But that is more me being pedantic. If you like you can simply ignore my comment.
Thanks Reviewed-by: Philipp Rudo prudo@redhat.com
On Wed, 28 Jun 2023 11:12:21 +0800 Coiby Xu coxu@redhat.com wrote:
The current estimated crashkernel is too small and leads to OOM for the LUKS case for both aarch64 4k and 64k kernels. For example, "kdumpctl estimate" gave the following output on a system, # kdumpctl estimate Encrypted kdump target requires extra memory, assuming using the keyslot with maximum memory requirement
Recommended crashkernel: 1217M Kernel image size: 47M Kernel modules size: 3M Initramfs size: 28M Runtime reservation: 64M LUKS required size: 1074M Large modules: xfs: 2002944If we subtract the LUKS required size 1074M from the estimated size 1217M, we have only 143M. The estimation about LUKS required size is accurate so it means "kdumpctl estimate" significantly underestimate the baseline value. "kdumpctl estimate" will compare the baseline value with the default crashkernel value and choose the bigger one. Since the default value doesn't take special cases like LUKS into consideration, the extra memory requirement should be excluded when comparing the baseline value with the default value.
Signed-off-by: Coiby Xu coxu@redhat.com
v2
- improve commit msg [Philipp]
kdumpctl | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kdumpctl b/kdumpctl index 58c18d21..12401042 100755 --- a/kdumpctl +++ b/kdumpctl @@ -1314,13 +1314,15 @@ do_estimate() echo -e "Encrypted kdump target requires extra memory, assuming using the keyslot with maximum memory requirement\n" fi
- estimated_size=$((kernel_size + mod_size + initrd_size + runtime_size + crypt_size))
estimated_size=$((kernel_size + mod_size + initrd_size + runtime_size)) if [[ $baseline_size -gt $estimated_size ]]; then recommended_size=$baseline_size else recommended_size=$estimated_size fi
recommended_size=$((recommended_size + crypt_size))
echo "Reserved crashkernel: $((reserved_size / size_mb))M" echo "Recommended crashkernel: $((recommended_size / size_mb))M" echo