如何将DPDK-ACL划分为多trie结构？

Question

我正在使用 DPDK-20.08 测试 DPDK-ACL 库性能。我已将数千条 acl 规则添加到 acl 上下文中，但仍然只有一个 trie。什么情况下可以拆分成multi-trie？

PS： 如果我将 rte_acl_config 中的 max_size 设置为小于所需的数字，则多次尝试后都会失败。

ACL: Gen phase for ACL ctx "ipv4_acl_0" exceeds max_size limit, bytes required: 38044176, allowed: 2097152
ACL: Build phase for ACL "ipv4_acl_0":
node limit for tree split: 16384
nodes created: 77950
memory consumed: 117440610
ACL: trie 0: number of rules: 4000, indexes: 4
ACL: Gen phase for ACL ctx "ipv4_acl_0" exceeds max_size limit, bytes required: 38044176, allowed: 2097152
ACL: Build phase for ACL "ipv4_acl_0":
node limit for tree split: 8192
nodes created: 77950
memory consumed: 117440610
ACL: trie 0: number of rules: 4000, indexes: 4
ACL: Gen phase for ACL ctx "ipv4_acl_0" exceeds max_size limit, bytes required: 38044176, allowed: 2097152
ACL: Build phase for ACL "ipv4_acl_0":
node limit for tree split: 4096
nodes created: 77950
memory consumed: 117440610
ACL: trie 0: number of rules: 4000, indexes: 4
ACL: Gen phase for ACL ctx "ipv4_acl_0" exceeds max_size limit, bytes required: 38044176, allowed: 2097152
ACL: Build phase for ACL "ipv4_acl_0":
node limit for tree split: 2048
nodes created: 77950
memory consumed: 117440610
ACL: trie 0: number of rules: 4000, indexes: 4
acl context <ipv4_acl_0>@0x10081fec0
  socket_id=0
  alg=3
  max_rules=4000
  rule_size=96
  num_rules=4000
  num_categories=0
  num_tries=0

Answer 1

一个大的 acl trie 的构建和更新速度很慢，因此我们为具有 16 位长掩码的网络创建一个 rte_acl_ctx[255] 数组，并通过 pkt 的 ip 地址的第三个字节（a.b.c.d 中的“c”）选择 rte_acl_ctx ，它有一点开销，但节省了大量构建 trie 的时间，从 3 秒到 300 毫秒。