I have a very small website, in a very competitive niche, that may receive a 100 hits a day, mostly for long tail keywords in blog posts. Yesterday and today I have been receiving dozens of hits per hour for the home page, where normally I might only have 2-3 hits per day for the home page.
The hits spend less than 15 seconds on the page, use different browsers, versions, resolutions and cities and are all direct (i.e., no referrals). There doesn't seem to be any common denominator to be able to identify or possibly block these hits.
From what I can determine, there's no real harm being done, unless it's simply to make my home page have a high bounce rate and negatively impact SEO.
Should I be concerned about these hits impacting SEO or is this some kind of penetration testing?