GP commits are the GPs' own money invested into the fund, typically 1 to 5% of total fund size. The commit is the most direct alignment signal a GP can offer LPs, they're putting their savings on the same outcomes. Larger commits are common in spinout funds and at firms where the GPs have accumulated wealth from prior funds.
The debate over the 'right' commit size (and how it should be funded, cash, fee waiver, loan) is ongoing. Most LPs view commit primarily as a fairness signal rather than a meaningful contribution to fund capital.