请教，为何我的网络频繁丢包

[weixin_38068246]

结构终端-》交换-》核心交换-》防火-》IPS-》路由器-》光模-》外网
ping路由器内网口，丢包率1～3%，ping路由器上一级设备（IPS或者防火）非常正常，查看路由器cpu的负载也不是很高，但是出错厉害的时候会导致彻底无法上网，能ping到内网口但无法连接外网。路由器曾经报错：
*Apr 12 02:32:44.074: %SYS-2-MALLOCFAIL: Memory allocation of 65536 bytes failed
from 0x6002A194, alignment 8
Pool: Processor  Free: 280036  Cause: Memory fragmentation
Alternate Pool: None  Free: 0  Cause: No Alternate pool
-Process= "IP Input", ipl= 3, pid= 75,  -Traceback= 0x60E02D30 0x60017064 0x600
1D1DC 0x6001D97C 0x6002A19C 0x600299F0 0x6002B898 0x6002966C 0x613E4728 0x613E4D
DC 0x613EEAD4 0x6140E910 0x61406D84 0x613D7A4C 0x6128C3FC 0x6128C580
*Apr 12 02:32:45.978: %SYS-2-CHUNKEXPANDFAIL: Could not expand chunk pool for NA
T Port Range. No memory available -Process= "Chunk Manager", ipl= 3, pid= 1,  -T
raceback= 0x60E02D30 0x600298D0
*Apr 12 02:32:55.982: %SYS-2-CHUNKEXPANDFAIL: Could not expand chunk pool for NA
T Port Range. No memory available -Process= "Chunk Manager", ipl= 3, pid= 1,  -T
raceback= 0x60E02D30 0x600298D0

重启后有所恢复，检查各项指标如下
Router#show proc cpu sorted
CPU utilization for five seconds: 17%/8%; one minute: 16%; five minutes: 8%
PID Runtime(ms)   Invoked      uSecs   5Sec   1Min   5Min TTY Process
  75       18052     98798        182  7.51%  7.66%  3.77%   0 IP Input
  35        2428       205      11843  1.19%  1.16%  0.59%   0 Per-Second Jobs
   4          88        20       4400  0.39%  0.05%  0.00%   0 Check heaps

Router#show proc memory sorted
Processor Pool Total:  164808960 Used:   34462380 Free:  130346580
      I/O Pool Total:   37748224 Used:   10618784 Free:   27129440
PID TTY  Allocated      Freed    Holding    Getbufs    Retbufs Process
   0   0   72480600   36930236   31730444          0          0 *Init*
   1   0   10253344          0   10260548          0          0 Chunk Manager
但是很快仍然会时断时续。上班时间丢包很严重，下班好很多。从本周开始的，之前虽然也有断，但没有这么厉害，现在几乎10秒就断一次。