---
title: Allgatherv算法4指定TCP传输，np大规格执行报错
description: "集合操作Allgatherv算法4执行传输模式为TCP，多节点满核启动进程报错："
url: https://www.hikunpeng.com/document/detail/zh/kunpenghpcs/hpckit/devg/userg_huaweimpi_0053.html
sourcePath: /source/zh/kunpenghpcs/hpckit/devg/userg_huaweimpi_0053.html
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---
# Allgatherv算法4指定TCP传输，np大规格执行报错

#### 现象描述

集合操作Allgatherv算法4执行传输模式为TCP，多节点满核启动进程报错：

运行失败示例如下：

mpirun --allow-run-as-root --timeout 350 -np 1024 -N 128 --hostfile ~/hmpifile_2021/hostfile/hf8 -x UCX_TLS=tcp -x UCG_PLANC_UCX_ALLGATHERV_ATTR=I:4 ~/hmpifile_2021/allgatherv/allgatherv

```
Authorized users only. All activities may be monitored and reported.
[hmpi03:04566] pml_ucx.c:428  Error: ucp_ep_create(proc=514) failed: Destination is unreachable
[hmpi03:04563] pml_ucx.c:428  Error: ucp_ep_create(proc=515) failed: Destination is unreachable
[1684893155.703980] [hmpi06:4797 :1]         tcp_cm.c:749  UCX  WARN  tcp_iface 0x3c6e6b10: connection establishment for socket fd 755 from <invalid address family> to 192.168.0.1:51311 was unsuccessful
[1684893155.703997] [hmpi06:4797 :1]         tcp_cm.c:749  UCX  WARN  tcp_iface 0x3c6e6b10: connection establishment for socket fd 755 from <invalid address family> to 192.168.0.1:51311 was unsuccessful
[1684893256.847887] [hmpi05:11722:0]         tcp_cm.c:705  UCX  ERROR tcp_ep 0x86843a0: reached maximum number of connection retries (25)
```


#### 可能原因

TCP建链产生的软中断重度负载，导致CPU无法处理，所以TCP建链超时。对于Allgatherv线性算法，为TCP本身的限制，属于正常现象。


#### 恢复步骤

Allgatherv使用TCP传输模式时，优先使用其他算法。