# Is mempool-cache-size effective in DPDK mode in Suricata?

**URL:** <https://forum.suricata.io/t/is-mempool-cache-size-effective-in-dpdk-mode-in-suricata/6101>\
**Category:** Developers\
**Tags:** community, suricata, dpdk\
**Created:** [November 6, 2025, 9:52am UTC](https://forum.suricata.io/t/is-mempool-cache-size-effective-in-dpdk-mode-in-suricata/6101 "2025-11-06T09:52:07Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![gongziw](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.suricata.io/gongziw/32/3323_2.png) [@gongziw](https://forum.suricata.io/u/gongziw)\
**Post date:** [November 6, 2025, 9:52am UTC](https://forum.suricata.io/t/is-mempool-cache-size-effective-in-dpdk-mode-in-suricata/6101/1 "2025-11-06T09:52:07Z")

</div>

Suricata: 8.0.1  
DPDK: 24.11.3

DPDK mempool per-lcore local cache uses `rte_lcore_id()` to get the index. This value is set in EAL worker threads, but is invalid in Suricata worker threads.

Suricata add log:

```auto
static TmEcode ReceiveDPDKThreadInit(ThreadVars *tv, const void *initdata, void **data)
{
/**/
// Add log
SCLogConfig("Dpdk lcore_id=%u", rte_lcore_id());
/**/
}

```

Ouputs:

```auto
Config: dpdk: Dpdk lcore_id=4294967295

```

DPDK add log:

```auto
static __rte_always_inline struct rte_mempool_cache *
rte_mempool_default_cache(struct rte_mempool *mp, unsigned lcore_id)
{
	if (mp->cache_size == 0) 
		return NULL;

	if (lcore_id >= RTE_MAX_LCORE) {
       // Add log
		RTE_MEMPOOL_LOG(ERR, "%s: lcore_id %u out of range", mp->name, lcore_id);
		return NULL;
	}

	rte_mempool_trace_default_cache(mp, lcore_id,
		&mp->local_cache[lcore_id]);
	return &mp->local_cache[lcore_id];
}

```

Outputs:

```auto
MEMPOOL: mempool_0000:00:13.0: lcore_id 4294967295 out of range

```

Suricata yaml dpdk config:

```auto
dpdk:
  eal-params:
    proc-type: primary
    log-level:
      - debug
      - bus.*:debug

  interfaces:
    - interface: 0000:00:13.0 
      threads: 1
      promisc: true 
      multicast: true 
      checksum-checks: false 
      checksum-checks-offload: true 
      mtu: 1500 
      mempool-size: 4096
      mempool-cache-size: 256
      rx-descriptors: 1024
      tx-descriptors: 1024

```

---

<div class="post-metadata">

**Author:** ![lukashino](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.suricata.io/lukashino/32/1150_2.png) [@lukashino](https://forum.suricata.io/u/lukashino)\
**Post date:** [November 6, 2025, 11:43am UTC](https://forum.suricata.io/t/is-mempool-cache-size-effective-in-dpdk-mode-in-suricata/6101/2 "2025-11-06T11:43:15Z")

</div>

Hi gongziw,

Thanks for reaching out. It does indeed look like it is not used, so converting threads to EAL-initialized threads makes sense. Since in 8, each thread has their own mempool, I don’t expect a big bump in performance, though I think it makes sense to convert to EAL threads anyway.

Ticket formed in [Feature #8084: dpdk: in dpdk runmode initiialize EAL threads - Suricata - Open Information Security Foundation](https://redmine.openinfosecfoundation.org/issues/8084)