LibHTP is a security-aware parser for the HTTP protocol and its related bits and pieces. In versions 0.5.50 and below, there is a traffic-induced memory leak that can starve the process of memory, leading to loss of visibility. To workaround this issue, set suricata.yaml app-layer.protocols.http.libhtp.default-config.lzma-enabled to false. This issue is fixed in version 0.5.51.