nfs环境搭建请参考《nfs环境》。
构造nfs断网不断写文件导致oom的场景:
systemctl stop nfs-server # 客户端可用，服务端不可用
while true
do
# 循环写
echo something > /mnt/file &
donefree -h命令统计内存，只看到used不断增加。
qemu虚拟机中导出vmcore的方法请参考《内核调试方法》，虚拟机导出vmcore对比，用crash解析，可以看出有大幅增加的只有USED:
# nfs刚挂载时
crash> kmem -i
PAGES TOTAL PERCENTAGE
TOTAL MEM 998421 3.8 GB ----
FREE 902099 3.4 GB 90% of TOTAL MEM
USED 96322 376.3 MB 9% of TOTAL MEM
SHARED 10513 41.1 MB 1% of TOTAL MEM
BUFFERS 1121 4.4 MB 0% of TOTAL MEM
CACHED 34971 136.6 MB 3% of TOTAL MEM
SLAB 19758 77.2 MB 1% of TOTAL MEM
TOTAL HUGE 0 0 ----
HUGE FREE 0 0 0% of TOTAL HUGE
TOTAL SWAP 0 0 ----
SWAP USED 0 0 0% of TOTAL SWAP
SWAP FREE 0 0 0% of TOTAL SWAP
COMMIT LIMIT 499210 1.9 GB ----
COMMITTED 128341 501.3 MB 25% of TOTAL LIMIT
# 快oom时
crash> kmem -i
PAGES TOTAL PERCENTAGE
TOTAL MEM 998421 3.8 GB ----
FREE 21024 82.1 MB 2% of TOTAL MEM
USED 977397 3.7 GB 97% of TOTAL MEM
SHARED 3197 12.5 MB 0% of TOTAL MEM
BUFFERS 78 312 KB 0% of TOTAL MEM
CACHED 3496 13.7 MB 0% of TOTAL MEM
SLAB 66520 259.8 MB 6% of TOTAL MEM
TOTAL HUGE 0 0 ----
HUGE FREE 0 0 0% of TOTAL HUGE
TOTAL SWAP 0 0 ----
SWAP USED 0 0 0% of TOTAL SWAP
SWAP FREE 0 0 0% of TOTAL SWAP
COMMIT LIMIT 499210 1.9 GB ----
COMMITTED 1391284 5.3 GB 278% of TOTAL LIMIT